When Youdao select-to-translate or the browser extension fails, branch by symptom: selection with no popup → check host access and whether another translator stole the event; grey / unclickable icon → extension disabled, needs page reload, or store update; only some sites fail → CSP, iframes, ad blockers, and enterprise policy; clicking the extension crash-quits the browser → crash / won’t open. For install and first-time enable steps, see the browser extension guide; full-page translate entry points sit in the webpage translation guide; blank simultaneous subtitle / softsub garble → subtitle translate failed.
Last week someone selected an English abstract in Edge and never got a popup. Site access was “On click” — they never clicked the icon first, so the selection never reached Youdao. Switching to “On all sites” and hard-refreshing fixed the same paragraph instantly. Another machine had two select-to-translate extensions fighting over shortcuts; leaving only Youdao restored the bubble.
This page covers “I already installed the extension, but select-to-translate / the plugin is dead now.” It is not a store-install walkthrough. Install failures and browser crash-quits belong in the extension guide and the crash article.
Split silence, grey icons, site blocks, and crashes
“Youdao select-to-translate” or “extension not working” in search usually means four things. Silent selection: highlighted text never shows a bubble. Grey icon: toolbar control is disabled, or the browser asks you to reload the page. Site conflict: public news works, intranet / banking / embedded PDF viewers fail. Crash: clicking the extension kills the tab or window — that is not a permission tweak.
Before changing settings, note browser and extension version, whether failure is “every site” or “one URL,” and whether other translators or ad blockers are on. Public page works, intranet fails → site policy. Every site silent → permissions and extension state. Instant quit → leave this article.
Skim the FAQ for install/account notes. Mobile voice, photo, and document fails are different threads — don’t fold them into one browser reinstall.
Extension permissions: host access and the “On click” trap
Chrome/Edge: Extensions → Youdao → Details → Site access. If it is “On click,” you must click the icon before selection events reach the extension. For always-on select-to-translate, switch to “On all sites” or allowlist the domains you use, then hard-refresh the tab (Ctrl/Cmd+Shift+R).
Firefox is similar: confirm multi-site / run on sites wasn’t turned off. Enterprise or parental policies sometimes lock extensions read-only — the icon stays grey forever until IT allows content-script injection.
Still no popup after granting access: select a short public Wikipedia paragraph. If that works, don’t reinstall — the current host is blocked. If public pages also fail, move to conflicts below.
Site conflicts: CSP, iframes, and ad blockers
Strict CSP hosts block extension injection: other sites work, this one never does. Banks, government portals, and some SaaS admin UIs are typical. A/B test in the same browser on a public article — public success means the extension is alive; for the failing host, paste into the desktop client instead.
Text inside iframes or embedded PDF viewers often isn’t the top-level document, so the extension never sees the selection. Open a plain HTML tab, or copy into the Youdao app. Ad blockers / privacy extensions with “block third-party scripts” can also kill the translate bubble — pause blocking on that site and retest once.
When only the full-page translate control greys out on one domain, run the same public-page check, then review blocker rules; how-to steps stay in the webpage translation guide.
Competing extensions: shortcuts and selection events
Two or more hover/select translators often fight over mouseup or shortcuts. Symptoms: another brand’s bubble flashes, Youdao never appears, or your hotkey opens a different product.
Fix: in the extension manager, disable other translators, leave only Youdao, reopen the tab, and select an 8–12 word English phrase. When Youdao’s popup is stable, re-enable others one by one. Don’t keep both on while loop-reinstalling Youdao — reinstalls don’t fix event stealing.
If a custom shortcut is owned by the OS or another extension, change it in the browser’s keyboard shortcuts page, then retest selection.
Grey icons and “reload required”: extension state
Grey toolbar icon with “can’t use on this page”: common on chrome://, store pages, new tabs, and local PDF files — switch to a normal https page. If the browser says reload is required, use Reload in the extension menu or close/reopen the tab.
Browsers sometimes auto-disable crashy or permission-changed extensions: re-enable in the manager and confirm you aren’t on a half-year-old sideload. Broken sideloads should come back via the store or the channels pointed from the download page.
If the options page opens and settings save, the extension process is mostly fine — fix permissions and conflicts before wiping all browser data.
When to reinstall — and how to divert crashes
Reinstall when a public page works on a coworker’s same browser but every https host on yours stays silent, or you know the package is a broken/outdated sideload. Flow: uninstall in the manager → restart the browser → reinstall from the store per the extension guide → set usable site access → select one phrase on a public page. Desktop builds can also be checked via the download page.
If clicking the extension or opening the Youdao client quits instantly, leave this article and use won’t open / crash. Need install/enable steps only → extension guide. After a clean install, single-host failures still point to CSP/blockers — stop the uninstall loop.
More platform notes sit under the FAQ and Guides — open the matching symptom page.