SUMMARY I have icons-only task manager setup and the restore Plasma session activated. As effect, several (four in this case) Dolphin instances are restored at startup. OBSERVED RESULT I have started two VLC instances and a Firefox instance. Firefox has no mute button on its icon. The multiple instances are collapse in one icon on the icons-only task manager bar. Dolphin icon has a mute button. VLC icon has a mute button. The bug consists in the fact that the mute button of Dolphin icon has effect over the first opened instance of VLC and that only. The mute button on the VLC icon seems to affect nothing (I don't have an instance of some application to be muted by it, apparently). Closing the second VLC instance removed the mute button from the Dolphin group icon. Also, its unclear which instance the mute button should operate on which instance, as there are many, but seems to work on one only. It's unclear if it is icons-only task manager related too. STEPS TO REPRODUCE Not sure of the sequence to open the instance of what application to get to the problem yet. EXPECTED RESULT The mute button should be assigned to a specific instance of an application or group of some kind and manage the application whose the icon belongs to. SOFTWARE/OS VERSIONS Operating System: Gentoo Linux KDE Plasma Version: 5.18.1 KDE Frameworks Version: 5.67.0 Qt Version: 5.14.1 Kernel Version: 5.4.0-sabayon OS Type: 64-bit Processors: 8 × Intel® Core™ i7 CPU 920 @ 2.67GHz Memory: 23,5 GiB of RAM ADDITIONAL INFORMATION
Opening a second VLC again would activate the mute button on the Dolphin icon again.
I see the pattern. The mute button is assigned to Dolphin because VLC is opened as effect of the file type association with VLC, by launching a file associated with VLC from Dolphin. I think it is not correct because Dolphin isn't the source of sound, but VLC.
*** This bug has been marked as a duplicate of bug 417457 ***