Not sure this is a solution but it worked for me. I started to temporarily rename files in Firefox that had update in them. One disabled the popup--but FF also installed version 78. I immediately did a system restore which reinstalled ver 68. Since then---no popup. So a flag got set somewhere that was not overwritten in the system restore that perhaps sensed ver 78 had been installed.
Give it a try.Creat a system restore (or a system backup) before you experiment to be safe,
hth
After I posted the above, i went over to Support. At the top was a thread about Ver 82 and moving the tab bar.
viewtopic.php?f=38&t=3066783The OP is inquired about Linux--so things might be different with my W7 Windows.