> Press ⇧⌘/ to search all of the current app's menu items. Then use the Up/Down arrow keys to navigate the results and press Return to execute that menu bar action.
Kinda like command palette for every app, I like it. Would be even better if it preselected the matching option.
Unfortunately, this is broken in Firefox – they’ve bound ⌘ ? to their help page, and it opens then immediately closes the Help menu. You can rebind it to something else (e.g. ⌥ ⇧ ⌘ /) in System Settings → Keyboard → Keyboard Shortcuts → App Shortcuts → Firefox, menu title: Get Help.
One other problem is, it doesn’t always find the command I’m looking for. E.g. when I typed “dev”, it didn’t show “Web Developer Tools” at first. I then checked Tools menu (it was there), then tried typing it in the Help menu again, and sure enough, it found it this time.