You might try BrowserPageActions, or "pageActionPanel" but i wouldn't know if the Mac keyboard macro thing is going to find it like a traditional menu - it isn't a menu with a menu ID, it's a "panel". If the same thing can turn up in a right-click context menu on the page, and a "menu" is required, then perhaps "pageActionContextMenu".

It may just be that you skip this, and add the actual menu item, which is "Share". (But it is listed as a panel item, not a menu item...) I do not have any "share" in my menu and checking the browser's chrome is a bit iffy as i am no expert. "BrowserPageActions.shareURL" could possibly cover it.

Maybe one of these will work. Otherwise, i would hope someone expert in the code and working of Firefox will answer.

I assume that this Share menu is created dynamically via JavaScript and I don't think there is a real path to open/access this menu. Even going to the page action menu via the keyboard on Windows/Linux requires to access the location bar and then press the Tab key to jump to the page actions container. You can use the cursor Left/Right keys to navigate in this container and press Enter to activate an item or open a sub menu.

For "Send Tab to Device" I see these elements in the Browser Toolbox: Page Action menu: toolbarbutton#pageAction-panel-sendToDevice (ID); label="Send Tab to Device" Panel that opens if I click this item: panelview#pageAction-panel-sendToDevice-subview (ID) Body of this panel: vbox#pageAction-panel-sendToDevice-subview-body (ID) Device in this panel: toolbarbutton.pageAction-sendToDevice-device (class); label="<name of device>"

• https://developer.mozilla.org/en-US/Tools/Browser_Toolbox

It does all look context-dependent and dynamically created, and no actual menu ids.

Thank you both for your help! Too bad it turns out there's no way to make a keyboard shortcut for this. But I'm glad to know for certain one way or another.