[MlMt] New Viewer Tab?

[Quinn Comendant]

Is there a way to open a new viewer in a tab instead of a new window via a hotkey?

I know I can set the system-wide setting “Prefer tabs always when opening documents” in System Preferences → General, but I only want to use tabs for message viewer; when reading or composing mail I still want to use individual windows.

I'm also aware if I show the tab bar, I can click the [+] button at the right side of the tab bar. I want to be able to do this with a hotkey.

Is there a way to move a window to a tab? (The reverse exists: a tab can be moved to a new window.)

Quinn