The part about running in menubar partially works with Close to menu bar option.
Shortcut keys though may not work as expected:
- ⌘+W doesn’t work: GitHub 714 + GitHub 802
- ⌘+Q will shut down entire app (expected?): GitHub 786
Someone had attempted to work on adding a menubar UI, but it was a bit clunky as it just embedded the full desktop app into the tray: Tray icon mini UI
I do see that a 3rd party has tried wrapping Bitwarden extension into a menubar-only Swift app (NOTE: this is not affiliated with Bitwarden): GitHub - jnsdrtlf/bitwarden-menubar: Bitwarden in the macOS menu bar
It would be interesting to see if something similar can be done in an Electron(JavaScript) App. Bitwarden already includes the browser plugin inside macOS Desktop app in order to support Safari. One issue would be if it is possible to sync info between the two UIs (i.e. single-sign-on, etc.).