diff --git a/tests/settingsUtcTimestamps.test.js b/tests/settingsUtcTimestamps.test.js
new file mode 100644
index 0000000..91526db
--- /dev/null
+++ b/tests/settingsUtcTimestamps.test.js
@@ -0,0 +1,111 @@
+// Tests for the UTC Timestamps setting.
+//
+// The checkbox was moved out of the Token Spam Protection well and into the
+// Display well next to the theme selector. It is wired by id through the $()
+// helper, so the move cannot break the handler — but nothing in the suite said
+// so. These tests pin both halves down: the markup lives in Display and
+// nowhere else, and the value still round-trips through storage.
+
+const fs = require("fs");
+const path = require("path");
+
+const POPUP_HTML = fs.readFileSync(
+ path.join(__dirname, "..", "src", "popup", "index.html"),
+ "utf8",
+);
+
+// The body of one `
` well, selected by its heading.
+function wellWithHeading(html, heading) {
+ const headingIndex = html.indexOf(
+ '
' + heading + "
",
+ );
+ expect(headingIndex).toBeGreaterThan(-1);
+ const start = html.lastIndexOf('
{
+ test("the checkbox appears exactly once in the popup markup", () => {
+ const matches = POPUP_HTML.match(/id="settings-utc-timestamps"/g);
+ expect(matches).toHaveLength(1);
+ });
+
+ test("it renders in the Display well, alongside the theme selector", () => {
+ const display = wellWithHeading(POPUP_HTML, "Display");
+
+ expect(display).toContain('id="settings-utc-timestamps"');
+ expect(display).toContain('id="settings-theme"');
+ });
+
+ test("it does not render in the Token Spam Protection well", () => {
+ const spam = wellWithHeading(POPUP_HTML, "Token Spam Protection");
+
+ expect(spam).not.toContain('id="settings-utc-timestamps"');
+ // The filters that do belong there are untouched.
+ expect(spam).toContain('id="settings-hide-low-holders"');
+ expect(spam).toContain('id="settings-hide-fraud-contracts"');
+ expect(spam).toContain('id="settings-hide-dust"');
+ expect(spam).toContain('id="settings-dust-threshold"');
+ });
+});
+
+describe("the UTC Timestamps setting round-trips through storage", () => {
+ let store;
+
+ function loadStateModule() {
+ store = {};
+ global.chrome = {
+ storage: {
+ local: {
+ get: async (key) =>
+ key in store ? { [key]: store[key] } : {},
+ set: async (obj) => Object.assign(store, obj),
+ },
+ },
+ };
+ jest.resetModules();
+ return require("../src/shared/state");
+ }
+
+ afterEach(() => {
+ delete global.chrome;
+ });
+
+ test("defaults to off with nothing persisted", async () => {
+ const { state, loadState } = loadStateModule();
+
+ await loadState();
+
+ expect(state.utcTimestamps).toBe(false);
+ });
+
+ test("an enabled checkbox is persisted and read back", async () => {
+ const first = loadStateModule();
+
+ // What the change handler in views/settings.js does.
+ first.state.utcTimestamps = true;
+ await first.saveState();
+ expect(store.autistmask.utcTimestamps).toBe(true);
+
+ // A fresh popup load sees it.
+ jest.resetModules();
+ const second = require("../src/shared/state");
+ expect(second.state.utcTimestamps).toBe(false);
+ await second.loadState();
+ expect(second.state.utcTimestamps).toBe(true);
+ });
+
+ test("turning it back off is persisted too", async () => {
+ const { state, saveState, loadState } = loadStateModule();
+
+ state.utcTimestamps = true;
+ await saveState();
+ state.utcTimestamps = false;
+ await saveState();
+
+ state.utcTimestamps = true;
+ await loadState();
+ expect(state.utcTimestamps).toBe(false);
+ });
+});