I installed today firefox-ubuntu-bin from the AUR so I can use the global menu with KDE Plasma.
First I had an error message with apparmor “Failed to start Load AppArmor profiles” at startup and shutdown, then I did a research and I found this solution and it worked.
Now I was trying to watch something on primevideo but Firefox complains about widevinecdm plugin crash.
Firefox and DRM worked fine before (but I’m not sure if it worked even with the firefox-ubuntu-bin before I solved the apparmor problem).
My main guess is that since this firefox is from the AUR maybe the widevine plugin is not in the correct place or linked correctly to the browser. But I can’t find anything similar to my case online.
Any good soul can help or guide me to a solution?
Thank you in advance to whoever has the patience to help
Update: I don’t really know how but it seems that the apparmor profile was the culprit since even uninstalling the AUR firefox version and installing the official one wasn’t helping.
So I deleted all what I did in this solution for the "Failed to start Load AppArmor profiles” error.
At this point I would again have had apparmor error if using the ubuntu version, then I installed the firefox-appmenu-bin from the AUR and it’s currently working as expected, even though I had to make GTK_USE_PORTAL=1 works again.
In conclusion, if someone follow this nice tutorial and decides to install the firefox-ubuntu-bin, be aware of the chance to see the apparmor error and that if you solve it (maybe that solution wasn’t good but the error disappeared) it might mess with widevinecdm.
Actually using the env variables wasn’t the hard part. The hassle was to track down why DRM didn’t work anymore.
I think that installing a firefox with appmenu and the gtk_use_portal in the manjaro kde edition by default would save users from a bit of hassle and improve the Plasma experience even more (so far on Manjaro I think we have the best KDE Plasma experience)