fix: show balances and fees below 0.000001 as nonzero on the send screens (closes #343 )

The stored ETH and token balances and the send-confirm screen's fee were each cut to six decimal places, and a token holding cut to zero was dropped, so a value below 0.000001 read as zero. Balances are now stored exactly, whatever decimals a token declares, and every nonzero token holding is kept; the balance check reads a token balance to its first 18 places. The balance lists, the send-screen token selector, the address total and the remove-address warning leave out a holding below 0.000001 themselves, through isBelowOneMillionth(). The send and send-confirm screens' balances, reserve and insufficient-balance messages go through truncateAmountNeverZero(). The send-confirm and approval screens both render the fee through formatFee(), which prices the exact fee in USD. Model: opus-5-5
2026-10-04 11:07:37 +02:00
20 changed files with 649 additions and 472 deletions
@@ -892,12 +892,21 @@ shows is a V4 exact-in `amountIn` of zero.
 The rule and its exception live in `src/shared/amountDisplay.js` as
 `truncateAmount()` and `truncateAmountNeverZero()`. Everything the approval and
 confirmation screens display goes through the floored one — the ERC-20 amount,
-the ETH value and max fee (`src/popup/views/approval.js`), and the swap's
-`Amount` and `Min. received` lines (`src/shared/uniswap.js`). The history and
-balance lists (`src/shared/transactions.js`) use the unfloored one: the
-transaction detail view is the authoritative record and already shows exact
-precision. The 4-decimal rule is unchanged everywhere else, including for
-amounts at or above the floor on the approval screens.
+the ETH value and max fee (`src/popup/views/approval.js`), the swap's `Amount`
+and `Min. received` lines (`src/shared/uniswap.js`), the Send screen's
+`Current balance` (`src/popup/views/send.js`), and the balance and network fee
+on the confirmation screen for the wallet's own send
+(`src/popup/views/confirmTx.js`). Both screens render a network fee through
+`formatFee()` in `src/popup/views/helpers.js`, which prices the exact fee in USD
+rather than its truncated figure, so the same fee reads the same on both, USD
+value included. Balances are stored exactly (`src/shared/balances.js`), whatever
+decimals a token declares, so a balance below the floor reaches these screens as
+it is. The history list (`src/shared/transactions.js`) uses the unfloored one:
+the transaction detail view is the authoritative record and already shows exact
+precision. The balance lists use neither: they round to four places with
+`toFixed(4)` (`balanceLine()` in `src/popup/views/helpers.js`). The 4-decimal
+rule is unchanged everywhere else, including for amounts at or above the floor
+on the approval screens.

 The floor applies only where the token's scale is known. Where it is not, the
 approval screen states base units instead of a quantity — see Unknown token
@@ -1055,8 +1064,13 @@ list from any other contract address is always dropped, and so is any token
 claiming a symbol that belongs to the native asset and therefore has no
 legitimate contract at all (`"ETH"`). That filter is unconditional — the "Hide
 tokens with fewer than 1,000 holders" setting governs the transaction history
-and the send-screen token selector, not this list. Tracked tokens with a zero
-balance are listed as well while "Show tracked tokens with zero balance" is on.
+and the send-screen token selector, not this list. `fetchTokenBalances()` stores
+every nonzero holding of a token it admits, however small, but a holding below
+0.000001 is left out of the balance lists, the send-screen token selector, the
+address total and the remove-address warning (`isBelowOneMillionth()` in
+`src/shared/amountDisplay.js`). The Send and confirmation screens show it when
+its token is the one being sent. Tracked tokens with a zero balance are listed
+as well while "Show tracked tokens with zero balance" is on.

 #### Stored state and its version

@@ -1244,10 +1258,7 @@ view would leave a wallet one click from deletion.
      of every wallet, deduplicated by hash and filtered. Each row is three
      lines: age and direction, then the counterparty's colour dot (with our own
      name for it, where it is one of our addresses) and the amount, then the
-      counterparty's full address on a row of its own. A contract creation has
-      no counterparty: its second line is the amount alone and its third line
-      says "This transaction creates a new contract. It has no recipient." The
-      transaction lists on AddressDetail and AddressToken draw the same rows
+      counterparty's full address on a row of its own
    - "Add additional wallet..." link at bottom
 - **Transitions**:
    - Tap address row → sets the active address and broadcasts
@@ -1440,9 +1451,7 @@ view would leave a wallet one click from deletion.
 - **Elements**:
    - "Transaction Broadcast" heading (no back button — tx is irreversible)
    - Amount + symbol
-    - To: color dot + full address + etherscan link; for a contract creation,
-      which has no recipient, "This transaction creates a new contract. It has
-      no recipient." instead
+    - To: color dot + full address + etherscan link
    - Transaction hash: full hash (tap to copy) + etherscan link
    - Count-up timer: "Waiting for confirmation... Ns"
 - **Behavior**: Polls `getTransactionReceipt` every 10 seconds. The wait is
@@ -1471,8 +1480,7 @@ view would leave a wallet one click from deletion.
    - Decoded action well (shown when the transaction carried recognized
      calldata; the top-level Amount and To are hidden in that case)
    - Amount + symbol
-    - To: color dot + full address + etherscan link, or for a contract creation
-      the same sentence as on WaitTx
+    - To: color dot + full address + etherscan link
    - Block number
    - Transaction hash: full hash (tap to copy) + etherscan link
    - "Done" button
@@ -1487,8 +1495,7 @@ view would leave a wallet one click from deletion.
 - **Elements**:
    - "Transaction Failed" heading
    - Amount + symbol
-    - To: color dot + full address + etherscan link, or for a contract creation
-      the same sentence as on WaitTx
+    - To: color dot + full address + etherscan link
    - Error message (dashed border box)
    - Transaction hash section (hidden if broadcast failed before getting hash):
      full hash (tap to copy) + etherscan link
@@ -1526,7 +1533,7 @@ view would leave a wallet one click from deletion.
    - From: blockie + color dot + full address (tap to copy) + etherscan link;
      ENS name if available
    - To: blockie + color dot + full address (tap to copy) + etherscan link; ENS
-      name if available. For a contract creation, the same sentence as on WaitTx
+      name if available
    - Time: ISO datetime + relative age in parentheses
    - Block: block number (tap to copy) + etherscan block link
    - Amount: value + symbol (bold)
@@ -1837,8 +1844,8 @@ view would leave a wallet one click from deletion.
    - Decoded action (if calldata is recognized): action name, token details,
      amounts, steps, deadline (see Transaction Decoding)
    - From: color dot + full address + etherscan link
-    - Contract: color dot + full address + etherscan link, token symbol label if
-      known; for a contract creation, the same sentence as on WaitTx
+    - Contract: color dot + full address + etherscan link (or "contract
+      creation"), token symbol label if known
    - Value: amount in ETH (4 decimal places, USD in parentheses)
    - Network fee (max): gas limit × fee per gas in ETH (4 decimal places, USD
      in parentheses), with the gas limit and the fee per gas in gwei below it
@@ -45,13 +45,23 @@ but the review is broader than any of them.

 # Completed Steps

- 2026-10-04: A transaction with no `to` says "This transaction creates a new
-  contract. It has no recipient." on its recipient line and in its transaction
-  history row ([#250](https://git.eeqj.de/sneak/AutistMask/issues/250)). The
-  wait, success and error screens, the transaction detail view and the history
-  rows on Home, AddressDetail and AddressToken showed a blank address there,
-  with a colour dot whose colour was `undefined`; the approval screen showed
-  "(contract creation)". A transaction with a real `to` is unchanged.
+- 2026-10-04: The Send and confirmation screens no longer show an ETH balance, a
+  token balance or a network fee below 0.000001 as zero
+  ([#343](https://git.eeqj.de/sneak/AutistMask/issues/343)). The stored balances
+  (`src/shared/balances.js`) and the confirmation screen's fee were each cut to
+  six decimal places by a rule of their own, and a token holding cut to zero was
+  dropped. Balances are now stored exactly, whatever decimals a token declares,
+  and every nonzero token holding is kept; the balance check reads a token
+  balance to its first 18 places, the most an amount can have. The balance
+  lists, the send-screen token selector, the address total and the
+  remove-address warning leave out a holding below 0.000001 themselves, as
+  before. The Send screen's `Current balance`, and the confirmation screen's
+  balance, fee, reserve and insufficient-balance messages, go through
+  `truncateAmountNeverZero()` in `src/shared/amountDisplay.js`, the helper the
+  approval screen already used. The confirmation and approval screens both
+  render the fee through `formatFee()` in `src/popup/views/helpers.js`, which
+  prices the exact fee in USD, so the same fee reads the same on both, USD value
+  included.

 - 2026-10-04: The flash line keeps to the one line it reserves at any message
  length ([#252](https://git.eeqj.de/sneak/AutistMask/issues/252)). A message
@@ -3,7 +3,7 @@ const {
    showView,
    showFlash,
    balanceLinesForAddress,
-    txCounterpartyHtml,
+    addressDotHtml,
    addressTitle,
    escapeHtml,
    displaySymbol,
@@ -233,13 +233,16 @@ function renderTransactions(txs) {
        // is shown whole; the title or ENS name, where there is one, names
        // it on the line above rather than replacing it.
        const nameStr = escapeHtml(title || ensName || "");
+        const addrStr = escapeHtml(counterparty);
+        const dot = addressDotHtml(counterparty);
        const err = tx.isError ? " (failed)" : "";
        const opacity = tx.isError ? " opacity:0.5;" : "";
        const ago = escapeHtml(timeAgo(tx.timestamp));
        const iso = escapeHtml(isoDate(tx.timestamp));
        html += `<div class="tx-row py-2 border-b border-border-light text-xs cursor-pointer hover:bg-hover" data-tx="${i}" style="${opacity}">`;
        html += `<div class="flex justify-between"><span class="text-muted" title="${iso}">${ago}</span><span>${dirLabel}${err}</span></div>`;
-        html += txCounterpartyHtml(counterparty, nameStr, amountStr);
+        html += `<div class="flex justify-between"><span class="flex items-center">${dot}${nameStr}</span><span>${amountStr}</span></div>`;
+        html += `<div class="am-address">${addrStr}</div>`;
        html += `</div>`;
        i++;
    }
@@ -6,7 +6,7 @@ const {
    showView,
    showFlash,
    flashCopyFeedback,
-    txCounterpartyHtml,
+    addressDotHtml,
    addressTitle,
    escapeHtml,
    displaySymbol,
@@ -309,13 +309,16 @@ function renderTransactions(txs) {
        // is shown whole; the title or ENS name, where there is one, names
        // it on the line above rather than replacing it.
        const nameStr = escapeHtml(title || ensName || "");
+        const addrStr = escapeHtml(counterparty);
+        const dot = addressDotHtml(counterparty);
        const err = tx.isError ? " (failed)" : "";
        const opacity = tx.isError ? " opacity:0.5;" : "";
        const ago = escapeHtml(timeAgo(tx.timestamp));
        const iso = escapeHtml(isoDate(tx.timestamp));
        html += `<div class="tx-row py-2 border-b border-border-light text-xs cursor-pointer hover:bg-hover" data-tx="${i}" style="${opacity}">`;
        html += `<div class="flex justify-between"><span class="text-muted" title="${iso}">${ago}</span><span>${dirLabel}${err}</span></div>`;
-        html += txCounterpartyHtml(counterparty, nameStr, amountStr);
+        html += `<div class="flex justify-between"><span class="flex items-center">${dot}${nameStr}</span><span>${amountStr}</span></div>`;
+        html += `<div class="am-address">${addrStr}</div>`;
        html += `</div>`;
        i++;
    }
@@ -1,7 +1,6 @@
 const {
    $,
    addressTitle,
-    CONTRACT_CREATION_TEXT,
    escapeHtml,
    showView,
    showError,
@@ -9,6 +8,7 @@ const {
    renderAddressHtml,
    attachCopyHandlers,
    onViewLeave,
+    formatFee,
 } = require("./helpers");
 const { state, saveState } = require("../../shared/state");
 const { networkByChainId } = require("../../shared/networks");
@@ -208,7 +208,7 @@ function showPhishingWarning(elementId, isPhishing) {
 // and the nonce. The background compares every one of them against the signed
 // artifact, so every one of them has to be on the screen — a number that is
 // verified but never displayed is verified against nothing the user agreed to.
-function showTxFee(approvedTx, ethPrice) {
+function showTxFee(approvedTx) {
    const network = networkByChainId(approvedTx.chainId);
    $("approve-tx-network").textContent = network
        ? network.name
@@ -216,12 +216,9 @@ function showTxFee(approvedTx, ethPrice) {

    const gasLimit = BigInt(approvedTx.gasLimit);
    const feePerGas = BigInt(approvedTx.maxFeePerGas || approvedTx.gasPrice);
-    const maxFeeEth = formatTxValue(formatEther(gasLimit * feePerGas));
-    const usdStr = formatUsd(
-        ethPrice ? parseFloat(maxFeeEth) * ethPrice : null,
-    );
-    $("approve-tx-fee").textContent =
-        maxFeeEth + " ETH" + (usdStr ? " (" + usdStr + ")" : "");
+    // Through formatFee(), as the confirmation screen's fee is, so the same
+    // fee reads the same on both.
+    $("approve-tx-fee").textContent = formatFee(gasLimit * feePerGas);

    let detail =
        gasLimit.toString() +
@@ -321,7 +318,7 @@ function showTxApproval(details) {
        toHtml += approvalAddressHtml(toAddr);
        $("approve-tx-to").innerHTML = toHtml;
    } else {
-        $("approve-tx-to").innerHTML = escapeHtml(CONTRACT_CREATION_TEXT);
+        $("approve-tx-to").innerHTML = escapeHtml("(contract creation)");
    }

    const ethValueFormatted = formatTxValue(
@@ -333,7 +330,7 @@ function showTxApproval(details) {
    $("approve-tx-value").textContent =
        ethValueFormatted + " ETH" + (usdStr ? " (" + usdStr + ")" : "");

-    showTxFee(approvedTx, ethPrice);
+    showTxFee(approvedTx);

    // Decode calldata (reuse decoded from above)
    const decodedEl = $("approve-tx-decoded");
@@ -15,6 +15,7 @@ const {
    attachCopyHandlers,
    goBack,
    onViewLeave,
+    formatFee,
 } = require("./helpers");
 const { state } = require("../../shared/state");
 const { getSignerForAddress } = require("../../shared/wallet");
@@ -31,6 +32,9 @@ const {
    transferAmountUnits,
 } = require("../../shared/transferAmount");
 const { assertWithinCeilings } = require("../../shared/approvalVerify");
+// The balance lines, the fee reserve and the insufficient-balance messages go
+// through it, as the approval screen's amounts do.
+const { truncateAmountNeverZero } = require("../../shared/amountDisplay");
 const {
    CODES,
    FEE_PENDING,
@@ -150,11 +154,17 @@ function show(txInfo) {
        $("confirm-balance").textContent =
            bal == null
                ? "unknown (" + symbol + ")"
-                : valueWithUsd(bal + " " + symbol, balUsd);
+                : valueWithUsd(
+                      truncateAmountNeverZero(bal) + " " + symbol,
+                      balUsd,
+                  );
    } else {
        const bal = txInfo.balance || "0";
        const balUsd = ethPrice ? parseFloat(bal) * ethPrice : null;
-        $("confirm-balance").textContent = valueWithUsd(bal + " ETH", balUsd);
+        $("confirm-balance").textContent = valueWithUsd(
+            truncateAmountNeverZero(bal) + " ETH",
+            balUsd,
+        );
    }

    // Check for warnings (synchronous local checks)
@@ -249,7 +259,7 @@ function renderValidation(txInfo) {
                : "Insufficient " +
                      symbol +
                      " balance. You have " +
-                      txInfo.tokenBalance +
+                      truncateAmountNeverZero(txInfo.tokenBalance) +
                      " " +
                      symbol +
                      " but are trying to send " +
@@ -262,7 +272,7 @@ function renderValidation(txInfo) {
    if (codes.includes(CODES.INSUFFICIENT_ETH)) {
        messages.push(
            "Insufficient balance. You have " +
-                txInfo.balance +
+                truncateAmountNeverZero(txInfo.balance || "0") +
                " ETH but are trying to send " +
                txInfo.amount +
                " ETH.",
@@ -305,14 +315,6 @@ function setVisible(id, visible) {
    $(id).style.visibility = visible ? "visible" : "hidden";
 }

-// A fee in wei as an ETH string, truncated to 6 decimal places.
-function formatFeeEth(wei) {
-    const parts = formatEther(wei).split(".");
-    const dec =
-        parts.length > 1 ? parts[1].slice(0, 6).replace(/0+$/, "") || "0" : "0";
-    return parts[0] + "." + dec + " ETH";
-}
-
 async function estimateGas(txInfo) {
    try {
        const provider = getProvider(state.rpcUrl, state.networkId);
@@ -359,26 +361,20 @@ async function estimateGas(txInfo) {
        // flight; a stale fee must not reach the screen or the balance check.
        if (pendingTx !== txInfo) return;

-        const ethPrice = getPrice("ETH");
-        const usd = (wei) =>
-            ethPrice ? parseFloat(formatEther(wei)) * ethPrice : null;
-
+        // The fee line goes through formatFee(), as the approval screen's
+        // does, so the same fee reads the same on both.
        if (estimateWei !== null && estimateWei < gasCostWei) {
-            $("confirm-fee-amount").textContent = valueWithUsd(
-                "~" + formatFeeEth(estimateWei),
-                usd(estimateWei),
-            );
+            $("confirm-fee-amount").textContent = "~" + formatFee(estimateWei);
            $("confirm-fee-reserve").textContent =
-                "up to " + formatFeeEth(gasCostWei) + " reserved";
+                "up to " +
+                truncateAmountNeverZero(formatEther(gasCostWei)) +
+                " ETH reserved";
            setVisible("confirm-fee-reserve", true);
        } else {
            // No spread to report: either there is no estimate, or the node
            // quotes a gas price at or above maxFeePerGas, so the expected
            // cost is not below the reserve. Show the reserve alone.
-            $("confirm-fee-amount").textContent = valueWithUsd(
-                formatFeeEth(gasCostWei),
-                usd(gasCostWei),
-            );
+            $("confirm-fee-amount").textContent = formatFee(gasCostWei);
            setVisible("confirm-fee-reserve", false);
        }
        feeStatus = FEE_KNOWN;
@@ -87,7 +87,8 @@ function recoveryPathText(wallet) {
 // AddressDetail, followed by the USD total when there is one to give — no
 // total line at all on testnet or before the first price fetch, and no figure
 // when every holding here is one with no price, since "$0.00" directly under
-// "This address holds a balance." is a contradiction.
+// "This address holds a balance." is a contradiction. A token holding below
+// 0.000001 does not count, as the lines below leave it out.
 function balanceWarningHtml(addr) {
    if (!addressHoldsFunds(addr)) return "&nbsp;";
    const line = formatAddressTotal(getAddressValue(addr));
@@ -12,6 +12,11 @@
 // escapeHtml lives in src/shared/html.js, where the escape and the
 // reasoning behind it are; it is re-exported below so views keep importing
 // it from here.
+const { formatEther } = require("ethers");
+const {
+    truncateAmountNeverZero,
+    isBelowOneMillionth,
+} = require("../../shared/amountDisplay");
 const { DEBUG } = require("../../shared/constants");
 const { escapeHtml } = require("../../shared/html");
 const { isDebug } = require("../../shared/log");
@@ -247,6 +252,19 @@ function unknownableAmount(balance) {
    return Number.isFinite(n) ? n : null;
 }

+// A network fee in wei as the confirmation and approval screens both show it:
+// the ETH figure through truncateAmountNeverZero(), then its USD value when the
+// ETH price is known. The USD value is of the exact fee, not of the truncated
+// figure.
+function formatFee(wei) {
+    const eth = formatEther(wei);
+    const ethPrice = getPrice("ETH");
+    const usd = ethPrice ? formatUsd(parseFloat(eth) * ethPrice) : "";
+    return (
+        truncateAmountNeverZero(eth) + " ETH" + (usd ? " (" + usd + ")" : "")
+    );
+}
+
 // One row of the balance list: symbol, quantity, fiat value.
 //
 // `symbol` is the ERC-20's own symbol() as the block explorer reported it,
@@ -292,6 +310,9 @@ function balanceLinesForAddress(addr, trackedTokens, showZero) {
    );
    const seen = new Set();
    for (const t of addr.tokenBalances || []) {
+        // A holding below 0.000001 is not listed, tracked or not. A tracked
+        // token then gets the zero row below while showZero is on.
+        if (isBelowOneMillionth(t.balance)) continue;
        // A null balance is a holding of an unstatable amount, not a holding
        // of zero, so the show-zero setting has no say over it: hiding it
        // would be asserting the zero nobody established. Anything that does
@@ -322,14 +343,16 @@ function balanceLinesForAddress(addr, trackedTokens, showZero) {
 }

 // Whether an address holds anything at all: ETH or any ERC-20 the wallet
-// knows about. Deliberately unrounded — the rendered lines round to four
-// decimals, so a dust balance displays as 0.0000 while still being real
-// money at a real address. Callers that warn about holdings must ask this,
-// not the rendered figure.
+// knows about, except a token holding below 0.000001, which the balance list
+// under the remove-address warning leaves out too. Deliberately unrounded —
+// the rendered lines round to four decimals, so a dust balance displays as
+// 0.0000 while still being real money at a real address. Callers that warn
+// about holdings must ask this, not the rendered figure.
 function addressHoldsFunds(addr) {
    if (!addr) return false;
    if (parseFloat(addr.balance || "0") > 0) return true;
    for (const t of addr.tokenBalances || []) {
+        if (isBelowOneMillionth(t.balance)) continue;
        // A null balance is a holding whose amount could not be stated —
        // balances.js drops a row of zero base units before the scale is
        // consulted, so a row that survived with no quantity is holding
@@ -408,29 +431,6 @@ function addressTitle(address, wallets) {
    return null;
 }

-// What every recipient line and history row says for a transaction with no
-// `to`. Such a transaction creates a contract, so there is no address to show,
-// and a blank line on these screens reads as a rendering fault.
-const CONTRACT_CREATION_TEXT =
-    "This transaction creates a new contract. It has no recipient.";
-
-// The last two lines of a transaction history row: the counterparty's colour
-// dot and name beside the amount, then its full address. A contract creation
-// the user sent has no counterparty (its `to` is ""), so its row has the
-// amount alone and the contract creation sentence in place of the address.
-function txCounterpartyHtml(address, nameHtml, amountHtml) {
-    if (!address) {
-        return (
-            `<div class="flex justify-between"><span></span><span>${amountHtml}</span></div>` +
-            `<div>${escapeHtml(CONTRACT_CREATION_TEXT)}</div>`
-        );
-    }
-    return (
-        `<div class="flex justify-between"><span class="flex items-center">${addressDotHtml(address)}${nameHtml}</span><span>${amountHtml}</span></div>` +
-        `<div class="am-address">${escapeHtml(address)}</div>`
-    );
-}
-
 // Render an address with color dot, optional ENS name, optional title,
 // and optional truncation. Title and ENS are shown as bold labels above
 // the full address.
@@ -637,13 +637,12 @@ module.exports = {
    balanceLinesForAddress,
    addressHoldsFunds,
    unknownableAmount,
+    formatFee,
    addressColor,
    addressDotHtml,
    escapeHtml,
    displaySymbol,
    addressTitle,
-    CONTRACT_CREATION_TEXT,
-    txCounterpartyHtml,
    formatAddressHtml,
    renderAddressHtml,
    copyableHtml,
@@ -6,7 +6,6 @@ const {
    isoDate,
    timeAgo,
    addressDotHtml,
-    txCounterpartyHtml,
    addressTitle,
    escapeHtml,
    displaySymbol,
@@ -123,13 +122,16 @@ function renderHomeTxList(ctx) {
        // names it on the line above rather than replacing it.
        const title = addressTitle(counterparty, state.wallets);
        const titleStr = title ? escapeHtml(title) : "";
+        const addrStr = escapeHtml(counterparty);
+        const dot = addressDotHtml(counterparty);
        const err = tx.isError ? " (failed)" : "";
        const opacity = tx.isError ? " opacity:0.5;" : "";
        const ago = escapeHtml(timeAgo(tx.timestamp));
        const iso = escapeHtml(isoDate(tx.timestamp));
        html += `<div class="home-tx-row py-2 border-b border-border-light text-xs cursor-pointer hover:bg-hover" data-tx="${i}" style="${opacity}">`;
        html += `<div class="flex justify-between"><span class="text-muted" title="${iso}">${ago}</span><span>${dirLabel}${err}</span></div>`;
-        html += txCounterpartyHtml(counterparty, titleStr, amountStr);
+        html += `<div class="flex justify-between"><span class="flex items-center">${dot}${titleStr}</span><span>${amountStr}</span></div>`;
+        html += `<div class="am-address">${addrStr}</div>`;
        html += `</div>`;
        i++;
    }
@@ -16,6 +16,10 @@ const { resolveTokenDecimals } = require("../../shared/approvalAmount");
 const { resolveSymbol } = require("../../shared/tokenList");
 const { isLowHolderCount } = require("../../shared/holders");
 const { isSpoofedSymbol } = require("../../shared/symbolSpoof");
+const {
+    truncateAmountNeverZero,
+    isBelowOneMillionth,
+} = require("../../shared/amountDisplay");
 const { getAddress } = require("ethers");

 const ZERO_ADDRESS = "0x0000000000000000000000000000000000000000";
@@ -125,6 +129,10 @@ function renderSendTokenSelect(addr) {
        (state.fraudContracts || []).map((a) => a.toLowerCase()),
    );
    for (const t of addr.tokenBalances || []) {
+        // A holding below 0.000001 is left out, as the balance lists leave it
+        // out. Its token's own screen can still send it: there
+        // state.selectedToken picks the token, not this list.
+        if (isBelowOneMillionth(t.balance)) continue;
        if (isSpoofedSymbol(t.symbol, t.address)) continue;
        if (fraudSet.has(t.address.toLowerCase())) continue;
        // An unknown holder count does not withhold a token the user holds:
@@ -150,7 +158,9 @@ function updateSendBalance() {
    const token = state.selectedToken || $("send-token").value;
    if (token === "ETH") {
        $("send-balance").textContent =
-            "Current balance: " + (addr.balance || "0") + " ETH";
+            "Current balance: " +
+            truncateAmountNeverZero(addr.balance || "0") +
+            " ETH";
    } else {
        const tb = (addr.tokenBalances || []).find(
            (t) => t.address.toLowerCase() === token.toLowerCase(),
@@ -167,7 +177,10 @@ function updateSendBalance() {
        $("send-balance").textContent =
            bal == null
                ? "Current balance: unknown (" + symbol + ")"
-                : "Current balance: " + bal + " " + symbol;
+                : "Current balance: " +
+                  truncateAmountNeverZero(bal) +
+                  " " +
+                  symbol;
    }
 }

@@ -7,7 +7,6 @@ const {
    showFlash,
    flashCopyFeedback,
    addressTitle,
-    CONTRACT_CREATION_TEXT,
    addressDotHtml,
    escapeHtml,
    isoDate,
@@ -95,18 +94,13 @@ function render() {
    $("tx-detail-hash").innerHTML = txHashHtml(tx.hash);

    const fromTitle = addressTitle(tx.from, state.wallets);
+    const toTitle = addressTitle(tx.to, state.wallets);
    $("tx-detail-from").innerHTML = txAddressHtml(
        tx.from,
        tx.fromEns,
        fromTitle,
    );
-    // A contract creation has no recipient: transactions.js gives it `to: ""`.
-    if (tx.to) {
-        const toTitle = addressTitle(tx.to, state.wallets);
-        $("tx-detail-to").innerHTML = txAddressHtml(tx.to, tx.toEns, toTitle);
-    } else {
-        $("tx-detail-to").innerHTML = escapeHtml(CONTRACT_CREATION_TEXT);
-    }
+    $("tx-detail-to").innerHTML = txAddressHtml(tx.to, tx.toEns, toTitle);

    // Exact amount (full precision, copyable)
    const detailSym = displaySymbol(tx.symbol);
@@ -4,7 +4,6 @@ const {
    $,
    showView,
    addressTitle,
-    CONTRACT_CREATION_TEXT,
    escapeHtml,
    renderAddressHtml,
    attachCopyHandlers,
@@ -59,10 +58,7 @@ function endWait() {
    }
 }

-// A contract creation reaches these screens with `to` as "" (approval.js
-// writes `to: toAddr || ""`).
 function toAddressHtml(address) {
-    if (!address) return escapeHtml(CONTRACT_CREATION_TEXT);
    const title = addressTitle(address, state.wallets);
    return renderAddressHtml(address, { title });
 }
@@ -206,9 +202,8 @@ function restoreWait() {
    if (!info || typeof info !== "object" || Array.isArray(info)) return false;
    // A string is the whole requirement: the empty string is what a
    // contract-deployment approval persists (approval.js writes `to: toAddr
-    // || ""`), an empty `to` renders as a contract creation and an empty
-    // amount renders harmlessly, so refusing it would abandon a wait the live
-    // path itself created.
+    // || ""`), and both fields render harmlessly when empty, so refusing it
+    // would abandon a wait the live path itself created.
    if (typeof info.to !== "string") return false;
    if (typeof info.amount !== "string") return false;
    if (typeof w.broadcastTime !== "number" || !isFinite(w.broadcastTime)) {
@@ -6,10 +6,10 @@
 // (`src/shared/uniswap.js`) — and a fix applied to one of them left the other
 // two showing a different number for the same value.
 //
-// The two functions below are the two policies, not two implementations of
-// one: summary lists truncate, and the screens that state what is being
-// authorized truncate with a floor. Keeping them adjacent is the point, so a
-// change to the rule cannot reach one screen and miss another.
+// The two truncation functions below are the two policies, not two
+// implementations of one: summary lists truncate, and the screens that state
+// what is being authorized truncate with a floor. Keeping them adjacent is the
+// point, so a change to the rule cannot reach one screen and miss another.

 // Truncate to exactly four decimal places. Truncation, never rounding: an
 // amount must never be displayed as larger than it is, so 0.99999 stays
@@ -43,4 +43,18 @@ function truncateAmountNeverZero(val) {
    return parts[0] + "." + parts[1].slice(0, sig + 1);
 }

-module.exports = { truncateAmount, truncateAmountNeverZero };
+// Whether a stored token balance is a holding below 0.000001. The balance
+// lists, the send-screen token selector, the address total and the
+// remove-address warning leave such a holding out; the Send and confirmation
+// screens show it when its token is the one being sent. Exact, because
+// src/shared/balances.js stores plain decimal digits: below 0.000001 the
+// balance reads "0.000000" and then more digits.
+function isBelowOneMillionth(balance) {
+    return typeof balance === "string" && balance.startsWith("0.000000");
+}
+
+module.exports = {
+    truncateAmount,
+    truncateAmountNeverZero,
+    isBelowOneMillionth,
+};
@@ -52,19 +52,16 @@ function requireNetworkId(networkId) {
    return net;
 }

-function formatBalance(wei) {
-    const eth = formatEther(wei);
-    const parts = eth.split(".");
-    if (parts.length === 1) return eth + ".0";
-    const dec = parts[1].slice(0, 6).replace(/0+$/, "") || "0";
-    return parts[0] + "." + dec;
-}
-
+// A token balance as an exact decimal string, never cut: a cut stores a small
+// nonzero holding as zero. fetchTokenBalances() stores every nonzero holding of
+// a token it admits, however small; the screens that leave out one below
+// 0.000001 decide that themselves, through isBelowOneMillionth() in
+// src/shared/amountDisplay.js.
 function formatTokenBalance(raw, decimals) {
    const val = formatUnits(raw, decimals);
    const parts = val.split(".");
    if (parts.length === 1) return val + ".0";
-    const dec = parts[1].slice(0, 6).replace(/0+$/, "") || "0";
+    const dec = parts[1].replace(/0+$/, "") || "0";
    return parts[0] + "." + dec;
 }

@@ -149,11 +146,7 @@ async function fetchTokenBalances(address, blockscoutUrl, trackedTokens) {
            const scale = known !== null ? known : decimals;
            // null is a holding of an amount that cannot be stated, which is
            // not the same as a holding of zero, and must never render as one.
-            // With a scale, the display filter proper applies: a balance that
-            // rounds to zero at six places is dust and is not listed. Without
-            // one there is no such judgement to make, and the row is kept.
            const bal = scale === null ? null : formatTokenBalance(raw, scale);
-            if (bal === "0.0") continue;
            // null means the explorer reported no count, which is not the
            // same as a count of zero.  This gate is not the low-holder
            // display filter: it has no user-facing off switch and governs
@@ -221,7 +214,9 @@ async function refreshBalances(
                provider
                    .getBalance(addr.address)
                    .then((bal) => {
-                        addr.balance = formatBalance(bal);
+                        // Exact, never cut: a cut here stores a small nonzero
+                        // balance as zero.
+                        addr.balance = formatEther(bal);
                        log.debugf("ETH balance", addr.address, addr.balance);
                    })
                    .catch((e) => {
@@ -1,6 +1,7 @@
 // Price fetching with 5-minute cache, USD formatting, value aggregation.

 const { getTopTokenPrices } = require("./tokenList");
+const { isBelowOneMillionth } = require("./amountDisplay");

 const PRICE_CACHE_TTL = 300000; // 5 minutes

@@ -78,6 +79,9 @@ function getAddressValue(addr) {
    let usd = parseFloat(addr.balance || "0") * prices.ETH;
    let partial = false;
    for (const token of addr.tokenBalances || []) {
+        // A holding below 0.000001 is left out, as the balance lists leave it
+        // out, so the total never counts a holding the list does not show.
+        if (isBelowOneMillionth(token.balance)) continue;
        // A null balance is a holding whose scale nothing knows, so it has no
        // quantity to price — but it is still a holding, and a total that
        // silently omits it would read as complete. That is exactly what
@@ -139,7 +139,15 @@ function validateTransfer({
    const feeFp = known ? feeWei : null;

    if (isErc20) {
-        const tokenFp = toFixedPoint(tokenBalance) ?? 0n;
+        // A token can declare more than 18 decimals, and its balance is
+        // stored with all of them. Only the first 18 places (SCALE_DECIMALS)
+        // are read: an amount with more was refused above, so the places
+        // after them cannot decide whether the amount fits.
+        const tokenText =
+            typeof tokenBalance === "string"
+                ? tokenBalance.replace(/(\.\d{18})\d+$/, "$1")
+                : tokenBalance;
+        const tokenFp = toFixedPoint(tokenText) ?? 0n;
        if (amountFp > tokenFp) codes.push(CODES.INSUFFICIENT_TOKEN);
        if (feeFp !== null && feeFp > ethFp) {
            codes.push(CODES.INSUFFICIENT_ETH_FOR_FEE);
@@ -1,315 +0,0 @@
-// The recipient line of a contract creation
-// (https://git.eeqj.de/sneak/AutistMask/issues/250).
-//
-// A transaction with no `to` creates a contract. The approval screen, the
-// wait, success and error screens, the transaction detail view and the
-// transaction history rows each say so in a sentence, where they used to show
-// a blank line (an empty address, with a colour dot whose colour was
-// `undefined`) or, on the approval screen, "(contract creation)". A
-// transaction with a real `to` still shows that address.
-//
-// Driven against a minimal DOM stub in the shape
-// tests/typedDataPermit.test.js uses.
-
-jest.mock("../src/shared/log", () => ({
-    log: {
-        debugf: () => {},
-        infof: () => {},
-        warnf: () => {},
-        errorf: () => {},
-    },
-    // The transaction detail view fetches on-chain details after drawing; an
-    // answer that is not ok leaves the drawn lines as they are.
-    debugFetch: async () => ({ ok: false }),
-    setRuntimeDebug: () => {},
-    isDebug: () => false,
-}));
-
-// The wait screen polls for a receipt; this one never arrives.
-jest.mock("../src/shared/balances", () => ({
-    getProvider: () => ({ getTransactionReceipt: () => new Promise(() => {}) }),
-    refreshBalances: () => {},
-}));
-
-// The history lists ask the explorer for their transactions and resolve ENS
-// names for them; here the explorer answers with mockHistory and no name
-// resolves.
-let mockHistory = [];
-jest.mock("../src/shared/transactions", () => ({
-    ...jest.requireActual("../src/shared/transactions"),
-    fetchRecentTransactions: async () => mockHistory,
-}));
-jest.mock("../src/shared/ens", () => ({
-    ...jest.requireActual("../src/shared/ens"),
-    resolveEnsNames: async () => new Map(),
-}));
-
-globalThis.chrome = {
-    storage: { local: { get: async () => ({}), set: async () => {} } },
-};
-
-const { state } = require("../src/shared/state");
-const approval = require("../src/popup/views/approval");
-const txStatus = require("../src/popup/views/txStatus");
-const transactionDetail = require("../src/popup/views/transactionDetail");
-const home = require("../src/popup/views/home");
-const addressDetail = require("../src/popup/views/addressDetail");
-const addressToken = require("../src/popup/views/addressToken");
-
-const SENTENCE =
-    "This transaction creates a new contract. It has no recipient.";
-
-const FROM = "0x0000000000000000000000000000000000000a11";
-const RECIPIENT = "0x66133E8ea0f5D1d612D2502a968757D1048c214a";
-const TX_HASH =
-    "0x85215772ed26ea8b39c2b3b18779030487efbe0b5fd7e882592b2f62b837be84";
-// Init code for a contract creation's data.
-const INIT_CODE = "0x600160005500";
-
-function makeElement(id) {
-    const classes = new Set();
-    const el = {
-        id,
-        textContent: "",
-        value: "",
-        innerHTML: "",
-        disabled: false,
-        style: {},
-        dataset: {},
-        classList: {
-            add: (...names) => names.forEach((n) => classes.add(n)),
-            remove: (...names) => names.forEach((n) => classes.delete(n)),
-            contains: (n) => classes.has(n),
-            toggle: (n, force) => {
-                const on = force === undefined ? !classes.has(n) : force;
-                if (on) classes.add(n);
-                else classes.delete(n);
-                return on;
-            },
-        },
-        addEventListener: () => {},
-        querySelectorAll: () => [],
-        appendChild: () => {},
-    };
-    // Views reach for .parentElement to hide whole sections.
-    Object.defineProperty(el, "parentElement", {
-        get: () => node(id + "-parent"),
-    });
-    return el;
-}
-
-function makeDocument() {
-    const els = new Map();
-    return {
-        getElementById(id) {
-            // The debug banner is created on demand by helpers.js; absent
-            // is the state a non-debug, non-testnet popup is in.
-            if (id === "debug-banner") return null;
-            if (!els.has(id)) els.set(id, makeElement(id));
-            return els.get(id);
-        },
-        createElement: () => makeElement("created"),
-        body: { prepend: () => {} },
-    };
-}
-
-function node(id) {
-    return globalThis.document.getElementById(id);
-}
-
-// The line a transaction with a real `to` shows: that address, and nothing
-// left over from an empty one.
-function expectAddressLine(html) {
-    expect(html).toContain(RECIPIENT);
-    expect(html).not.toContain(SENTENCE);
-    expect(html).not.toContain("undefined");
-}
-
-beforeEach(() => {
-    globalThis.document = makeDocument();
-    globalThis.window = { location: { search: "" } };
-    state.wallets = [];
-    state.trackedTokens = [];
-    state.viewData = {};
-    state.viewStack = [];
-    state.currentView = null;
-    txStatus.init({ doRefreshAndRender: () => {} });
-});
-
-afterEach(() => {
-    txStatus.endWait();
-});
-
-// Open the transaction approval screen the way the popup does: the background
-// hands over the populated transaction and show() draws it.
-async function openTxApproval(to, data) {
-    globalThis.chrome.runtime = {
-        connect: () => ({ postMessage: () => {} }),
-        sendMessage: (msg, reply) => {
-            if (!reply) return;
-            if (msg.type !== "AUTISTMASK_GET_APPROVAL") return reply(null);
-            reply({
-                type: "tx",
-                hostname: "dapp.example",
-                isPhishingDomain: false,
-                approvedFrom: FROM,
-                approvedTx: {
-                    type: 2,
-                    from: FROM,
-                    chainId: "0x1",
-                    nonce: "0x7",
-                    gasLimit: "0x5208",
-                    maxPriorityFeePerGas: "0x3b9aca00",
-                    maxFeePerGas: "0x77359400",
-                    to,
-                    value: "0x0",
-                    data,
-                    accessList: [],
-                },
-            });
-        },
-    };
-    approval.init({});
-    await approval.show(1);
-}
-
-describe("the transaction approval screen", () => {
-    test("a contract creation says so instead of naming a contract", async () => {
-        await openTxApproval(null, INIT_CODE);
-        expect(node("approve-tx-to").innerHTML).toBe(SENTENCE);
-    });
-
-    test("a transaction with a recipient shows its address", async () => {
-        await openTxApproval(RECIPIENT, "0x");
-        expectAddressLine(node("approve-tx-to").innerHTML);
-    });
-});
-
-// approval.js carries a contract creation to these screens with `to` as "".
-describe("the wait, success and error screens", () => {
-    const creation = {
-        to: "",
-        amount: "0.0000",
-        token: "ETH",
-        tokenSymbol: null,
-    };
-    const transfer = { ...creation, to: RECIPIENT };
-
-    test("a contract creation says so on the wait screen", () => {
-        txStatus.showWait(creation, TX_HASH);
-        expect(node("wait-tx-to").innerHTML).toBe(SENTENCE);
-    });
-
-    test("a transaction with a recipient shows its address on the wait screen", () => {
-        txStatus.showWait(transfer, TX_HASH);
-        expectAddressLine(node("wait-tx-to").innerHTML);
-    });
-
-    test("a contract creation says so on the success and error screens", () => {
-        state.viewData = {
-            amount: "0.0000",
-            symbol: "ETH",
-            to: "",
-            hash: TX_HASH,
-            blockNumber: 1,
-        };
-        txStatus.renderSuccess();
-        expect(node("success-tx-to").innerHTML).toBe(SENTENCE);
-
-        txStatus.showError(creation, TX_HASH, "The transaction failed.");
-        expect(node("error-tx-to").innerHTML).toBe(SENTENCE);
-    });
-
-    test("a transaction with a recipient shows its address on the success and error screens", () => {
-        state.viewData = {
-            amount: "0.0050",
-            symbol: "ETH",
-            to: RECIPIENT,
-            hash: TX_HASH,
-            blockNumber: 1,
-        };
-        txStatus.renderSuccess();
-        expectAddressLine(node("success-tx-to").innerHTML);
-
-        txStatus.showError(transfer, TX_HASH, "The transaction failed.");
-        expectAddressLine(node("error-tx-to").innerHTML);
-    });
-});
-
-// A transaction FROM sent, as the history lists hold it. The explorer reports a
-// contract creation with no `to`, which src/shared/transactions.js turns into
-// `to: ""`.
-function historyTx(to) {
-    return {
-        hash: TX_HASH,
-        from: FROM,
-        to,
-        value: "0.0000",
-        exactValue: "0.0",
-        rawAmount: "0",
-        rawUnit: "wei",
-        symbol: "ETH",
-        timestamp: 1790000000,
-        isError: false,
-        directionLabel: "Sent",
-        direction: "sent",
-        contractAddress: null,
-    };
-}
-
-// The detail view is opened with the transaction a history row holds.
-describe("the transaction detail view", () => {
-    test("a contract creation says so", () => {
-        transactionDetail.show(historyTx(""));
-        expect(node("tx-detail-to").innerHTML).toBe(SENTENCE);
-        expect(node("tx-detail-type").textContent).toBe("Contract Creation");
-    });
-
-    test("a transaction with a recipient shows its address", () => {
-        transactionDetail.show(historyTx(RECIPIENT));
-        expectAddressLine(node("tx-detail-to").innerHTML);
-    });
-});
-
-// The same rows are drawn on Home, AddressDetail and AddressToken (for ETH).
-describe.each([
-    ["Home", "home-tx-list", () => home.render({})],
-    ["AddressDetail", "tx-list", () => addressDetail.show()],
-    ["AddressToken", "address-token-tx-list", () => addressToken.show()],
-])("the transaction history on %s", (_name, listId, open) => {
-    async function rowsFor(tx) {
-        mockHistory = [tx];
-        open();
-        // The list is drawn once the history has been fetched.
-        await new Promise((resolve) => setTimeout(resolve, 0));
-        return node(listId).innerHTML;
-    }
-
-    beforeEach(() => {
-        state.wallets = [
-            {
-                name: "Main",
-                type: "key",
-                addresses: [{ address: FROM, balance: "0.0000" }],
-            },
-        ];
-        state.selectedWallet = 0;
-        state.selectedAddress = 0;
-        state.selectedToken = "ETH";
-    });
-
-    test("a contract creation's row says so, with no colour dot and no address line", async () => {
-        const html = await rowsFor(historyTx(""));
-        expect(html).toContain(SENTENCE);
-        expect(html).not.toContain("background:");
-        expect(html).not.toContain("am-address");
-        expect(html).not.toContain("undefined");
-    });
-
-    test("a transaction with a recipient shows its colour dot and address", async () => {
-        const html = await rowsFor(historyTx(RECIPIENT));
-        expectAddressLine(html);
-        expect(html).toContain("background:#");
-        expect(html).toContain(`<div class="am-address">${RECIPIENT}</div>`);
-    });
-});
@@ -1463,9 +1463,10 @@ test("an over-long flash message keeps to one line (#252)", async (env) => {
 // on opposite sides of the reserve while sitting on the same side of the
 // estimate.

-// The balance the funded fixture serves, and the amounts sent against it.
+// The balance the funded fixture serves, as the Send and confirmation screens
+// show it, and the amounts sent against it.
 const FUNDED_ETH_WEI = 10n ** 18n;
-const FUNDED_ETH_TEXT = "1.0";
+const FUNDED_ETH_TEXT = "1.0000";
 const COMFORTABLE_AMOUNT = "0.1";
 const OVER_BALANCE_AMOUNT = "2.0";

@@ -1479,7 +1480,7 @@ const GAP_AMOUNT = formatEther(FUNDED_ETH_WEI - FEE_ESTIMATE_WEI);
 // fee test: it covers the expected cost to the wei and falls short of the
 // reserve, so the same swap flips this assertion too — through a different
 // balance and a different message than the ETH path uses.
-const TOKEN_BALANCE_TEXT = "1.5";
+const TOKEN_BALANCE_TEXT = "1.5000";
 const TOKEN_AMOUNT = "0.25";
 const OVER_TOKEN_AMOUNT = "9.0";
 const FEE_ONLY_ETH_WEI = FEE_ESTIMATE_WEI;
@@ -1488,16 +1489,15 @@ function toHexWei(wei) {
    return "0x" + wei.toString(16);
 }

-// A fee in wei as the confirmation screen writes it. Deliberately a second
-// implementation of formatFeeEth() from src/popup/views/confirmTx.js rather
-// than an import of it: that module pulls in the whole popup and cannot be
-// required outside a browser, and asserting against an independent rendering
-// is stronger than asserting a function equals itself.
+// A fee in wei as the confirmation screen writes it: truncated to four decimal
+// places (README.md, Display Consistency). Deliberately a second
+// implementation rather than an import of src/shared/amountDisplay.js:
+// asserting against an independent rendering is stronger than asserting a
+// function equals itself. The fixture's fees are above 0.0001 ETH, so the
+// nonzero floor never applies here.
 function feeEth(wei) {
-    const parts = formatEther(wei).split(".");
-    const dec =
-        parts.length > 1 ? parts[1].slice(0, 6).replace(/0+$/, "") || "0" : "0";
-    return parts[0] + "." + dec + " ETH";
+    const [whole, frac = ""] = formatEther(wei).split(".");
+    return whole + "." + (frac + "0000").slice(0, 4) + " ETH";
 }

 // What the confirmation screen is showing right now, read out of the DOM in
@@ -1554,11 +1554,10 @@ async function backToAddress(page) {

 // Drive the popup to the confirmation screen for one send.
 //
-// It waits for the send screen to be showing `balance` before filling
-// anything in. That figure is the exact number the spend gate compares
-// against, so waiting for it — rather than for a refresh to have probably
-// landed — is what keeps every assertion below deterministic after a
-// fixture change.
+// It waits for the send screen to be showing `balance`, the fixture's balance
+// as that screen displays it, before filling anything in. Waiting for it —
+// rather than for a refresh to have probably landed — is what keeps every
+// assertion below deterministic after a fixture change.
 async function goToConfirm(page, { token, balance, amount }) {
    await backToAddress(page);
    await page.click("#btn-send");
@@ -0,0 +1,452 @@
+// The balance and fee lines of the Send and confirmation screens, and the fee
+// line they must share with the approval screen.
+//
+// An ETH balance, a token balance or a fee below 0.000001 rendered as zero on
+// these screens (https://git.eeqj.de/sneak/AutistMask/issues/343): the stored
+// balances and the fee were each cut to six decimal places, a rule of their
+// own, and a token holding cut to zero was dropped, while the approval screen
+// showed the same fee through src/shared/amountDisplay.js with the nonzero
+// floor. The balances are now stored exactly, every nonzero token holding
+// kept, and the screens show them and the fee through that helper.
+//
+// Driven through the real refreshBalances(), Send screen, confirmation screen
+// and approval screen, with only the node, the explorer and the DOM stubbed: a
+// balance written onto state by hand would skip the place the cut happened.
+
+"use strict";
+
+// What the stub node answers. Each test sets what it needs.
+const mockNode = {
+    balanceWei: 0n,
+    feeData: { maxFeePerGas: 1n, gasPrice: 1n },
+};
+
+// The token rows the stub explorer reports for the address.
+const mockExplorer = { items: [] };
+
+jest.mock("ethers", () => {
+    const actual = jest.requireActual("ethers");
+    class StubProvider {
+        async getBalance() {
+            return mockNode.balanceWei;
+        }
+        async lookupAddress() {
+            return null;
+        }
+        async getFeeData() {
+            return mockNode.feeData;
+        }
+        async estimateGas() {
+            return 21000n;
+        }
+        async getCode() {
+            return "0x";
+        }
+        async getTransactionCount() {
+            return 1;
+        }
+    }
+    return {
+        ...actual,
+        JsonRpcProvider: StubProvider,
+        Network: { from: () => ({}) },
+    };
+});
+
+jest.mock("../src/shared/log", () => ({
+    log: {
+        debugf: () => {},
+        infof: () => {},
+        warnf: () => {},
+        errorf: () => {},
+    },
+    // The explorer's token list, which refreshBalances() also fetches.
+    debugFetch: jest.fn(async () => ({
+        ok: true,
+        status: 200,
+        json: async () => mockExplorer.items,
+    })),
+    setRuntimeDebug: () => {},
+    isDebug: () => false,
+}));
+
+// The confirmation screen's Etherscan label lookup is the only fetch() these
+// screens make; it fails, as it does offline.
+global.fetch = jest.fn(() => {
+    throw new Error("tests must not perform network requests");
+});
+
+// The approval the background hands the approval screen. Set per test.
+let approvalDetails = null;
+
+const { makeStorageStub } = require("./support/storageStub");
+global.chrome = {
+    storage: makeStorageStub(),
+    runtime: {
+        connect: () => ({
+            postMessage() {},
+            disconnect() {},
+            onDisconnect: { addListener() {} },
+        }),
+        sendMessage(message, callback) {
+            callback(
+                message.type === "AUTISTMASK_GET_APPROVAL"
+                    ? approvalDetails
+                    : undefined,
+            );
+        },
+    },
+};
+
+// A stub DOM: every id resolves to a recording element.
+const elements = new Map();
+
+function makeEl(id) {
+    const handlers = new Map();
+    return {
+        id,
+        textContent: "",
+        innerHTML: "",
+        value: "",
+        disabled: false,
+        style: {},
+        dataset: {},
+        classList: {
+            add() {},
+            remove() {},
+            toggle() {},
+            contains: () => false,
+        },
+        handlers,
+        children: [],
+        addEventListener(name, fn) {
+            handlers.set(name, fn);
+        },
+        appendChild(child) {
+            this.children.push(child);
+            return child;
+        },
+        querySelectorAll: () => [],
+        querySelector: () => null,
+        remove() {},
+        focus() {},
+    };
+}
+
+global.document = {
+    getElementById(id) {
+        if (!elements.has(id)) elements.set(id, makeEl(id));
+        return elements.get(id);
+    },
+    createElement: (tag) => makeEl(tag),
+    body: { prepend() {}, appendChild() {} },
+    addEventListener() {},
+};
+global.navigator = { clipboard: { writeText() {} } };
+
+const { refreshBalances } = require("../src/shared/balances");
+const { state } = require("../src/shared/state");
+const {
+    prices,
+    clearPrices,
+    formatAddressTotal,
+    getAddressValue,
+} = require("../src/shared/prices");
+const send = require("../src/popup/views/send");
+const confirmTx = require("../src/popup/views/confirmTx");
+const approval = require("../src/popup/views/approval");
+const {
+    addressHoldsFunds,
+    balanceLinesForAddress,
+} = require("../src/popup/views/helpers");
+
+const HOLDER = "0x" + "a".repeat(40);
+const RECIPIENT = "0xC0FfEE0000000000000000000000000000c0fFEe";
+
+// 0.0000005 ETH, or 0.0000005 of an 18-decimal token.
+const HALF_MICRO_ETH = 500000000000n;
+
+// A token the bundled list does not know.
+const TOKEN = "0x" + "d".repeat(40);
+
+// The explorer's row for TOKEN, holding `value` base units. With only five
+// holders, it is listed only when the user tracks the token.
+function tokenRow(value, token = {}) {
+    return {
+        value: String(value),
+        token: {
+            type: "ERC-20",
+            address_hash: TOKEN,
+            symbol: "TOK",
+            name: "Token",
+            decimals: "18",
+            holders_count: "5",
+            ...token,
+        },
+    };
+}
+
+function text(id) {
+    return global.document.getElementById(id).textContent;
+}
+
+function errors() {
+    return global.document.getElementById("confirm-errors").innerHTML;
+}
+
+// The ETH balance the node reports and the token rows the explorer reports,
+// fetched and stored exactly where the popup stores them.
+async function refreshWith(balanceWei, tokenItems = []) {
+    mockNode.balanceWei = balanceWei;
+    mockExplorer.items = tokenItems;
+    state.wallets = [{ name: "Wallet 1", addresses: [{ address: HOLDER }] }];
+    state.selectedWallet = 0;
+    state.selectedAddress = 0;
+    await refreshBalances(
+        state.wallets,
+        "https://rpc.example.invalid",
+        "https://blockscout.example/api/v2",
+        state.trackedTokens,
+        "mainnet",
+    );
+}
+
+// Press Review on the Send screen for a send of `token` ("ETH" or a token
+// address), and show the confirmation screen it leads to with its fee estimate
+// settled.
+async function confirmSend(amount, token = "ETH") {
+    let txInfo = null;
+    send.init({ showConfirmTx: (info) => (txInfo = info) });
+    state.selectedToken = token;
+    global.document.getElementById("send-to").value = RECIPIENT;
+    global.document.getElementById("send-amount").value = amount;
+    await global.document
+        .getElementById("btn-send-review")
+        .handlers.get("click")();
+    confirmTx.show(txInfo);
+    for (let i = 0; i < 10; i++) await new Promise((r) => setTimeout(r, 0));
+}
+
+// The approval screen for a dApp transaction of 21000 gas, the gas the stub
+// node estimates for the send above.
+async function approveTxWithFeePerGas(maxFeePerGas) {
+    approvalDetails = {
+        type: "tx",
+        hostname: "dapp.example",
+        approvedFrom: HOLDER,
+        approvedTx: {
+            to: RECIPIENT,
+            value: "0",
+            data: "0x",
+            chainId: "0x1",
+            gasLimit: "21000",
+            maxFeePerGas: String(maxFeePerGas),
+            nonce: 0,
+        },
+    };
+    await approval.show("1");
+}
+
+beforeEach(() => {
+    elements.clear();
+    state.selectedToken = null;
+    state.trackedTokens = [];
+    state.fraudContracts = [];
+    state.currentView = null;
+    mockNode.feeData = { maxFeePerGas: 1n, gasPrice: 1n };
+});
+
+describe("an ETH balance below 0.000001 never renders as zero", () => {
+    test("on the Send screen", async () => {
+        await refreshWith(HALF_MICRO_ETH);
+        state.selectedToken = "ETH";
+        send.updateSendBalance();
+        expect(text("send-balance")).toBe("Current balance: 0.0000005 ETH");
+    });
+
+    test("on the confirmation screen", async () => {
+        await refreshWith(HALF_MICRO_ETH);
+        await confirmSend("0.0000001");
+        expect(text("confirm-balance")).toBe("0.0000005 ETH");
+    });
+
+    test("while a balance above the floor keeps four decimals", async () => {
+        await refreshWith(1234567890000000000n);
+        await confirmSend("0.1");
+        expect(text("confirm-balance")).toBe("1.2345 ETH");
+    });
+});
+
+// A token the user tracks stays on the balance list when the explorer's row is
+// dropped, so a holding of it below 0.000001 reached these screens as zero, and
+// the send was checked against zero.
+describe("a tracked token holding below 0.000001 never renders as zero", () => {
+    beforeEach(() => {
+        state.trackedTokens = [
+            { address: TOKEN, symbol: "TOK", name: "Token", decimals: 18 },
+        ];
+    });
+
+    test("on the Send screen", async () => {
+        await refreshWith(10n ** 18n, [tokenRow(HALF_MICRO_ETH)]);
+        state.selectedToken = TOKEN;
+        send.updateSendBalance();
+        expect(text("send-balance")).toBe("Current balance: 0.0000005 TOK");
+    });
+
+    test("on the confirmation screen, which checks the send against it", async () => {
+        await refreshWith(10n ** 18n, [tokenRow(HALF_MICRO_ETH)]);
+        await confirmSend("0.0000005", TOKEN);
+        expect(text("confirm-balance")).toBe("0.0000005 TOK");
+        expect(errors()).toBe("");
+        await confirmSend("0.0000006", TOKEN);
+        expect(errors()).toContain(
+            "You have 0.0000005 TOK but are trying to send 0.0000006 TOK.",
+        );
+    });
+
+    // The stored balance keeps all 24 places, and the balance check reads the
+    // first 18 of them rather than refusing it as no balance at all.
+    test("with more than 18 decimals, the send is checked against 18 of them", async () => {
+        state.trackedTokens[0].decimals = 24;
+        // 1.5 plus one base unit.
+        const value = 15n * 10n ** 23n + 1n;
+        await refreshWith(10n ** 18n, [tokenRow(value, { decimals: "24" })]);
+        await confirmSend("1.5", TOKEN);
+        expect(text("confirm-balance")).toBe("1.5000 TOK");
+        expect(errors()).toBe("");
+    });
+
+    test("with more than 18 decimals and a holding below 10^-18", async () => {
+        state.trackedTokens[0].decimals = 24;
+        // One base unit, 0.000000000000000000000001 TOK.
+        await refreshWith(10n ** 18n, [tokenRow(1n, { decimals: "24" })]);
+        state.selectedToken = TOKEN;
+        send.updateSendBalance();
+        expect(text("send-balance")).toBe(
+            "Current balance: 0.000000000000000000000001 TOK",
+        );
+        await confirmSend("0.000000000000000001", TOKEN);
+        expect(text("confirm-balance")).toBe("0.000000000000000000000001 TOK");
+        expect(errors()).toContain(
+            "You have 0.000000000000000000000001 TOK but are trying to send" +
+                " 0.000000000000000001 TOK.",
+        );
+    });
+});
+
+// A token the user does not track, with enough holders to be admitted. The
+// balance fetch dropped a holding of it below 0.000001, but the token stays
+// selected while its own screen is open: after sending 2 of a 2.0000003
+// holding, the user is back on that screen, and Send read the missing row as
+// zero.
+describe("an untracked token holding below 0.000001 never renders as zero", () => {
+    const row = () => tokenRow(HALF_MICRO_ETH, { holders_count: "50000" });
+
+    test("on the Send screen", async () => {
+        await refreshWith(10n ** 18n, [row()]);
+        state.selectedToken = TOKEN;
+        send.updateSendBalance();
+        expect(text("send-balance")).toBe("Current balance: 0.0000005 TOK");
+    });
+
+    test("on the confirmation screen, which checks the send against it", async () => {
+        await refreshWith(10n ** 18n, [row()]);
+        await confirmSend("0.0000005", TOKEN);
+        expect(text("confirm-balance")).toBe("0.0000005 TOK");
+        expect(errors()).toBe("");
+        await confirmSend("0.0000006", TOKEN);
+        expect(errors()).toContain(
+            "You have 0.0000005 TOK but are trying to send 0.0000006 TOK.",
+        );
+    });
+});
+
+// The fetch keeps every holding, so the screens that showed only what it kept
+// leave out a holding below 0.000001 themselves, and look as they did.
+describe("a token holding below 0.000001 is still not listed", () => {
+    afterEach(() => {
+        clearPrices();
+    });
+
+    test("for a token the user does not track", async () => {
+        prices.ETH = 3000;
+        await refreshWith(0n, [
+            tokenRow(HALF_MICRO_ETH, { holders_count: "50000" }),
+        ]);
+        const addr = state.wallets[0].addresses[0];
+        expect(balanceLinesForAddress(addr, [], true)).not.toContain(TOKEN);
+        expect(balanceLinesForAddress(addr, [], false)).not.toContain(TOKEN);
+        send.renderSendTokenSelect(addr);
+        const options = global.document.getElementById("send-token").children;
+        expect(options.map((o) => o.value)).toEqual([]);
+        // Not an unpriced token in the total, and not funds on the
+        // remove-address warning.
+        expect(formatAddressTotal(getAddressValue(addr))).toBe("Total: $0.00");
+        expect(addressHoldsFunds(addr)).toBe(false);
+    });
+
+    // As a tracked token holding nothing: listed only while zero balances are
+    // shown.
+    test("for a tracked token, unless zero balances are shown", async () => {
+        state.trackedTokens = [
+            { address: TOKEN, symbol: "TOK", name: "Token", decimals: 18 },
+        ];
+        await refreshWith(0n, [tokenRow(HALF_MICRO_ETH)]);
+        const addr = state.wallets[0].addresses[0];
+        expect(
+            balanceLinesForAddress(addr, state.trackedTokens, false),
+        ).not.toContain(TOKEN);
+        expect(
+            balanceLinesForAddress(addr, state.trackedTokens, true),
+        ).toContain(`data-token="${TOKEN}"`);
+    });
+});
+
+describe("a fee below 0.000001 ETH never renders as zero", () => {
+    test("when the estimate and the reserve are the same", async () => {
+        await refreshWith(10n ** 18n);
+        await confirmSend("0.1");
+        // 21000 gas at 1 wei is 0.000000000000021 ETH, shown to its first
+        // significant digit.
+        expect(text("confirm-fee-amount")).toBe("0.00000000000002 ETH");
+    });
+
+    test("when they differ, on both lines", async () => {
+        mockNode.feeData = { maxFeePerGas: 2n, gasPrice: 1n };
+        await refreshWith(10n ** 18n);
+        await confirmSend("0.1");
+        expect(text("confirm-fee-amount")).toBe("~0.00000000000002 ETH");
+        expect(text("confirm-fee-reserve")).toBe(
+            "up to 0.00000000000004 ETH reserved",
+        );
+    });
+});
+
+// The confirmation screen shows the reserve alone when the node quotes no
+// cheaper estimate, and that reserve is the same gas limit times maximum fee
+// per gas that the approval screen calls the max fee. An ETH price is set, as
+// it is on mainnet, so the USD value has to match too.
+describe("the same fee reads the same on the confirmation and approval screens", () => {
+    beforeEach(() => {
+        prices.ETH = 3000;
+    });
+    afterEach(() => {
+        clearPrices();
+    });
+
+    test.each([
+        // 21000 gas at 1 wei.
+        ["below the floor", 1n, "0.00000000000002 ETH (< $0.01)"],
+        // 0.001235294117631 ETH, which is $3.71. Pricing the truncated
+        // 0.0012 instead would read $3.60.
+        ["with more than four decimals", 58823529411n, "0.0012 ETH ($3.71)"],
+    ])("%s", async (_label, feePerGas, expected) => {
+        mockNode.feeData = { maxFeePerGas: feePerGas, gasPrice: feePerGas };
+        await refreshWith(10n ** 18n);
+        await confirmSend("0.1");
+        expect(text("confirm-fee-amount")).toBe(expected);
+        await approveTxWithFeePerGas(feePerGas);
+        expect(text("approve-tx-fee")).toBe(expected);
+    });
+});
@@ -389,7 +389,7 @@ describe("a scale the explorer's own rows disagree about", () => {
        expect(txInfo.tokenBalance).toBe("5.0");
        confirmTx.show(txInfo);
        await settle();
-        expect(text("confirm-balance")).toBe("5.0 NOVEL");
+        expect(text("confirm-balance")).toBe("5.0000 NOVEL");
        expect(errors()).toBe("");
        expect(sendDisabled()).toBe(false);
    });
@@ -431,7 +431,7 @@ describe("the confirmation screen tells an unknown balance from a zero one", ()
        const zero = await render("0.0");
        expect(unknown.balance).not.toBe(zero.balance);
        expect(unknown.balance).toBe("unknown (NOVEL)");
-        expect(zero.balance).toBe("0.0 NOVEL");
+        expect(zero.balance).toBe("0.0000 NOVEL");
    });

    // Both hit INSUFFICIENT_TOKEN — an unknown balance is treated as nothing to
@@ -443,7 +443,7 @@ describe("the confirmation screen tells an unknown balance from a zero one", ()
        expect(unknown.errors).not.toBe(zero.errors);
        expect(unknown.errors).toContain("This token&#39;s balance is unknown");
        expect(unknown.errors).not.toContain("You have");
-        expect(zero.errors).toContain("You have 0.0 NOVEL");
+        expect(zero.errors).toContain("You have 0.0000 NOVEL");
        expect(zero.errors).not.toContain("balance is unknown");
    });
 });