Remove suffix, don't alert on download cancel

popup.js

@@ -9,6 +9,11 @@ function setStatus(message) {
   statusEl.textContent = message;
 }
 
+function isUserCancelledError(result) {
+  const error = result && typeof result.error === "string" ? result.error.toLowerCase() : "";
+  return error.includes("canceled by the user") || error.includes("cancelled by the user");
+}
+
 function entryLabel(entry) {
   return entry && entry.fullUrl ? "full candidate" : "preview fallback";
 }
@@ -115,6 +120,9 @@ function buildRow(entry) {
   download.addEventListener("click", async () => {
     const result = await browser.runtime.sendMessage({ type: "DOWNLOAD_ENTRY", entry });
     if (!result || !result.ok) {
+      if (isUserCancelledError(result)) {
+        return;
+      }
       window.alert((result && result.error) || "Download failed.");
       return;
     }