Thank you for giving these issues attention. Here is the results of me
following up on some of these items.
1. I can confirm that settings fixes the issue. Adding the following onto the
default compton command resolves this issue with the transparent box around
the menus:
--shadow-exclude "class_g = 'Firefox' && argb" --shadow-exclude "class_g =
'Abrowser' && argb" --shadow-exclude "class_g = 'Icedove' && argb"
--shadow-exclude "class_g = 'IceCat' && argb"
This fixes the issue in Abrowser, Icedove, IceCat and Tor Browser. If there
are any more firefox based applications they may need to be added to this.
Where can I make changes to the default compton script? I don't believe that
/etc/compton.conf is used since the running process has this in the command:
--config /dev/null
It looks like all of the parameters are just on a single command as
arguments.
3. I tested torbrowser-launcher from the PPA and it works exactly as expected
with no issues.
4. Here is a bug report for this package in Ubuntu 18.04:
https://bugs.launchpad.net/ubuntu/+source/libsdl2/+bug/1775067
