Rated 5 out of 5 stars

I'm using BetterBird and this add-on doesn't seem to be working for me. I do not see the button "Mark" appear on the top right of the screen. I just can't highlight anything. The add-on does appear in my settings correctly.

Post-Review Comment: The developer's suggestion worked! I have now changed my rating to reflect this outcome.

This review is for a previous version of the add-on (6.0.0). 

In some cases the button does not appear automatically after the Add-on installation (I don’t know why). Then you can right-click on the toolbar, choose “Customize …”, then the Mark button should appear in the list and can be dragged to the toolbar.