Fix#27466
The problem is that any item in the menu could be hidden, pure CSS won't
work, and dropdown's builtin "hideDividers" doesn't work with our "scope
dividers". The newly introduced "archived" label makes the dividers
regression more.
None of the frontend js/ts files was touched besides these two commands
(edit: no longer true, I touched one file in
61105d0618
because of a deprecation that was not showing before the rename).
`tsc` currently reports 778 errors, so I have disabled it in CI as
planned.
Everything appears to work fine.