Click buttons quickly in some forms will submit repeated/duplicated requests

[wxiaoguang]

Description

All Gitea versions. Click buttons quickly in Issue form will submit repeated requests.

• https://try.gitea.io/wxiaoguang/test/issues/1#issuecomment-91921
• And there are so many related issues ...

About UI/UX: because there is no UI feedback to users and the buttons are still clickable, when there is a laggy network, user may click buttons multiple times, then there will be many duplicated comments.

Related PRs (but it still needs more work)

• Prevent double click new issue/pull/comment button #16157 , it prevents the create issue/pr and create comment button from double-clicked.
• Add loading status to submit buttons #10459 , partially replaced by Prevent double click new issue/pull/comment button #16157

Remaining works:

• check and prevent repeated requests for other forms
• prevent repeated requests for AJAX requests

Screenshots

NOTICE: This issue is not completely fixed. Some buttons have been fixed by #16157, but this issue is out-dated, so close it.

[delvh]

I would say that is the same error as #6859 on another form.
This seems to be a general submission problem.

[silverwind]

I think a proper solution would be to interject all form submissions via JS, stop them and re-execute them via fetch. This can be used to prevent duplicate submission and more importantly enables to show a potential error message/toast without a page reload.

[wxiaoguang]

Some buttons have been fixed by #16157, this issue is out-dated, so close it.