Install topic tree addon.
Switch to notebook tab or use three dots/addons/submenu/topic tree icon.
This opens the notebook tab.
Close FF by:
|||menu at bottom of Android tree, showing all open apps. Swipe FF away.
Reopen FF. Now, the browserAction menu entry is gone, while the addon is still installed (addon details can be shown).
Happens both on a Samsung Note 10 lite and a S7 tablet.
Trying to open via recently closed tabs gives a white screen.