Follow:
* #23574
* Remove all ".tooltip[data-content=...]"
Major changes:
* Remove "tooltip" class, use "[data-tooltip-content=...]" instead of
".tooltip[data-content=...]"
* Remove legacy `data-position`, it's dead code since last Fomantic
Tooltip -> Tippy Tooltip refactoring
* Rename reaction attribute from `data-content` to
`data-reaction-content`
* Add comments for some `data-content`: `{{/* used by the form */}}`
* Remove empty "ui" class
* Use "text color" for SVG icons (a few)
* Like #22851
* All other dropdown menu elements do not have such `hidden` class.
* Actually the dropdown menu elements do not need it in HTML, so this PR
removes it.
* There is already `.ui.dropdown .menu { display: none; }`, so when
loading the page, the menu is correctly hidden initially, no need to add
any more CSS classes.
* The Fomantic UI's `.hidden` class should still exist until there is no
its checkbox/dropdown module anymore. The Fomantic UI JS code still
addes `hidden` for `ui checkbox` and addes `transition hidden` for `ui
menu` at the moment.
* This PR also cleans the legacy inline `style`, which is quite hacky
and no need anymore.
All these dropdown menus work well.
I have tested these 5 places:
* The code search from User Profile
* The issue sidebar to lock issue
* The repo search form
* The repo setting page: branch list
* The repo setting page: merge option list
Screenshot:
![image](https://user-images.githubusercontent.com/2114189/218534515-e7dfe291-6765-4e0b-833c-b74f17e30117.png)