Fix aria.js bugs: incorrect role element problem, mobile focus problem, tippy problem (#23450)

This PR is extracted from #23346 to address some unclear (I don't
understand) code-belonging concerns.

This PR needs to be backported, otherwise the `aria.js` is too buggy in
some cases. Since there would be two minor conflicts, I will do the
backport manually.

Before: the `aria.js` is still buggy in some cases.

After: tested with AppleVoice, Android TalkBack

* Fix incorrect dropdown init code
* Fix incorrect role element (the menu role should be on the `$menu`
element, but not on the `$focusable`)
* Fix the focus-show-click-hide problem on mobile. Now the language menu
works as expected
* Fix incorrect dropdown template function setting
* Clarify the logic in aria.js
* Hide item's tippy after menu gets hidden
* Fix incorrect tippy `setProps` after `destroy`
* Fix UI lag problem when page gets redirected during menu hiding
animation with screen reader
* Improve comments
* Implement the layout proposed by #19861

<details>


d74a7efb60/web_src/js/features/aria.md (L38-L47)

</details>

web_src/js/features/common-global.js

@@ -89,9 +89,14 @@ export function initGlobalCommon() {
 
   // Semantic UI modules.
   const $uiDropdowns = $('.ui.dropdown');
-  $uiDropdowns.filter(':not(.custom)').dropdown({
-    fullTextSearch: 'exact'
-  });
+
+  // do not init "custom" dropdowns, "custom" dropdowns are managed by their own code.
+  $uiDropdowns.filter(':not(.custom)').dropdown({fullTextSearch: 'exact'});
+
+  // The "jump" means this dropdown is mainly used for "menu" purpose,
+  // clicking an item will jump to somewhere else or trigger an action/function.
+  // When a dropdown is used for non-refresh actions with tippy,
+  // it must have this "jump" class to hide the tippy when dropdown is closed.
   $uiDropdowns.filter('.jump').dropdown({
     action: 'hide',
     onShow() {
@@ -101,17 +106,23 @@ export function initGlobalCommon() {
     },
     onHide() {
       this._tippy?.enable();
+
+      // hide all tippy elements of items after a while. eg: use Enter to click "Copy Link" in the Issue Context Menu
+      setTimeout(() => {
+        const $dropdown = $(this);
+        if ($dropdown.dropdown('is hidden')) {
+          $(this).find('.menu > .item').each((_, item) => {
+            item._tippy?.hide();
+          });
+        }
+      }, 2000);
     },
-    fullTextSearch: 'exact'
-  });
-  $uiDropdowns.filter('.slide.up').dropdown({
-    transition: 'slide up',
-    fullTextSearch: 'exact'
-  });
-  $uiDropdowns.filter('.upward').dropdown({
-    direction: 'upward',
-    fullTextSearch: 'exact'
   });
+
+  // special animations/popup-directions
+  $uiDropdowns.filter('.slide.up').dropdown({transition: 'slide up'});
+  $uiDropdowns.filter('.upward').dropdown({direction: 'upward'});
+
   attachDropdownAria($uiDropdowns);
 
   attachCheckboxAria($('.ui.checkbox'));