[wxiaoguang]

ref: #40289 (comment)

[silverwind]

The ExclusiveFetch state handling looks correct. One regression in the Actions polling:

1. Network failures of the 1s polls now show a sticky error toast, the old code ignored them on purpose (e instanceof TypeError). Firefox rejects in-flight fetches with NetworkError on navigation and download clicks, so "Download logs" or an artifact link on a running run leaves a toast behind, as does a single dropped poll. Fix: if (!details.response) return; at the top of both polling callbacks, which keeps the toast for preview and diff.
2. loadCurrentRun no longer sends data: {}, so the binder reports Unsupported Content-Type on every summary poll. It only works because ViewPost ignores HasError. Fix: restore data: {}.

Written by Claude (Fable 5.2).

[wxiaoguang]

1. Network failures of the 1s polls now show a sticky error toast,

If you dislike it, you can remove it. Or, hide it when next fetch succeeds. Update: see below #40312 (comment)

2. loadCurrentRun no longer sends data: {},

Good catch. I have checked it when refactoring but it seems that I indeed missed it again

[wxiaoguang]

1. Network failures of the 1s polls now show a sticky error toast,

If you dislike it, you can remove it. Or, hide it when next fetch succeeds.

Added {duration: 2500} for error toasts.

Now the error message can tell end users why the loading fails, and won't bother end users for a too long time.

[wxiaoguang]

1. Network failures of the 1s polls now show a sticky error toast, the old code ignored them on purpose (e instanceof TypeError). Firefox rejects in-flight fetches with NetworkError on navigation and download clicks, so "Download logs" or an artifact link on a running run leaves a toast behind, as does a single dropped poll. Fix: if (!details.response) return; at the top of both polling callbacks, which keeps the toast for preview and diff.

0139da2 uses isNetworkError to ignore network errors. Such network errors seem useless to end users.

[silverwind]

State handling and polling look good, both earlier points are addressed.

1. The new in-flight tracking has no test. If the finally reset breaks, both Actions pollers silently stop. Fix: in fetch.test.ts, add expect(exclusiveFetch.isInFlight()).toBe(false); right after the /new request.
2. {duration: 2500} on the one-shot preview and diff toasts makes stale panel content look current once the toast fades. Suggestion: keep the sticky default there and the short duration only for the 1s polls.

Written by Claude (Opus 5.5).

[wxiaoguang]

• {duration: 2500} on the one-shot preview and diff toasts makes stale panel content look current once the toast fades. Suggestion: keep the sticky default there and the short duration only for the 1s polls.

I intentionally didn't use 1s. It will cause race and UI flash if the server error keep happening.