The download icon appears in the toolbar only when there are active or recent downloads and is hidden on intial startup of firefox.
A similar function for addons made for specific websites should be implemented.
Switching to a page with i.e. youtube.com/* should show show all my yt related addons manually pinned in the toolbar and then hide them when I switch to another page.
I also thought maybe a separate floating toolbar could be pinned in the upper right hand corner of the webpage as well (adjusted to the number of visible icons and hidden when empty of course).
This in itself can possibly be an addon (if adjusting the toolbar is allowed for addons).
...the overflow is okay, but not very convenient.
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