Add "jump to top" option on canvas

Is your feature request related to a problem? Please describe.
The /tc (table of contents) is a great feature for pages/canvasses have a lot of content. I think a “jump to top” option would be great addition.

Describe the solution you’d like
An (^) icon at the bottom left (or right for right-to-left languages) that is always visible like the (?) help icon.

Describe alternatives you’ve considered
The headings could be made clickable to jump back to the top. Maybe this can be combined with a request for deeplinks to allow not only to link to #top but also to any header like the TOC is basically doing.

Additional context