Use HTML headings for viewlet titles.

related to #52805

related to #52805

fixes #50292

use Shift-keybindings to workaround eager list/tree keybindings, move picker when visible and focus changes

related to #53773

related to #53773

Close param hints if you reach out of bounds of list instead of cycling

Fixes #34307

* Fix bug causing recommendations to sometimes appear in two places

* Naming

* Group fetch stage calls

also greatly reduce the amount of recreation for menubar changes

Fixes #53019

* adding context change listener and buffering calls to setup the menu

* addressing feedback