Follow:
* #23345
The branch/tag selector dropdown mixes jQuery/Fomantic UI/Vue together,
it's very diffcult to maintain and causes unfixable a11y problems. It
also causes problems like #19851#21314#21952
This PR is the first step for the refactoring, move `data-` attributes
to JS object and use Vue data as much as possible.
The old selector `'.choose.reference .dropdown'` was also wrong, it hits
`<div class="choose reference"><svg class="dropdown icon">` and would
cause undefined behaviors.
I have done some quick tests and it works. After this PR gets merged, I
will move the code into a Vue SFC in next PR.
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Co-authored-by: techknowlogick <techknowlogick@gitea.io>