Bubble timeline should be optional

Instance admin should be able to disable the bubble timeline entirely.

if empty the bubble timeline is hidden from the timeline list and the about page on pleroma-fe*

It is still present on the top navbar.

that’d be because it’s a core feature

I thought that since it was gone from the timeline sidebar that it should also be gone from the top navbar when empty, since it’s effectively the same as Home timeline when nothing is added.