diff --git a/src/background/index.js b/src/background/index.js
index 46314e7..fc1e330 100644
--- a/src/background/index.js
+++ b/src/background/index.js
@@ -89,19 +89,32 @@ function requestApproval(origin, hostname) {
         pendingApprovals[id] = { origin, hostname, resolve };
 
         const popupUrl = runtime.getURL("src/popup/index.html?approval=" + id);
-        windowsApi.create(
-            {
+        const popupWidth = 400;
+        const popupHeight = 500;
+
+        // Center the popup over the focused window so macOS keeps it
+        // on the same Space instead of switching desktops.
+        windowsApi.getLastFocused((currentWin) => {
+            const opts = {
                 url: popupUrl,
                 type: "popup",
-                width: 400,
-                height: 500,
-            },
-            (win) => {
+                width: popupWidth,
+                height: popupHeight,
+            };
+            if (currentWin) {
+                opts.left = Math.round(
+                    currentWin.left + (currentWin.width - popupWidth) / 2,
+                );
+                opts.top = Math.round(
+                    currentWin.top + (currentWin.height - popupHeight) / 2,
+                );
+            }
+            windowsApi.create(opts, (win) => {
                 if (win) {
                     pendingApprovals[id].windowId = win.id;
                 }
-            },
-        );
+            });
+        });
     });
 }