Add at least one more shortcut action for direct community activation

No shortcut action to switch to community 9 (as counted from the top of the list).

Let's say there are (custom) shortcuts resembling the built-ins, but starting from 0. ctrl 0 goes to messages, ctrl 8 goes to the eighth community. So there should be a corresponding action for ctrl 9. Whether there should be a few more, I am not so sure but I finish with two more things to consider.

Additional rationale: in a desktop environment especially, you can see this many community icons in most cases, so it does not seem excessive. The default "next community", ctrl tab shortcut, is not necessarily available in web contexts.