The action “directly pushing an application like firefox.desktop from the menu into the frontpanel” is lost. You only can do it via pushing the application to the desktop and then pull it into the frontpanel. Why is this option lost since plasma6? The taskmanager can display it but once an application is put there you can’t dismiss it by configurating the taskmanager (and removing it). If you want to dismiss an application from the taskmanager you have to edit
the ~/.config/plasma-org.kde.plasma.desktop-appletsrc and remove it from the launchers directive:
[code]
[Containments][2][Applets][90][Configuration][General]
hideLauncherOnStart=true
launchers=
separateLaunchers=false
[/code]
I think it’s a bug. As soon as you insert an activityswitch and define activitiers, the dialog “remove from taskmanager” is shown as “add to taskmanager” (despite always been added).
Adding to taskmanager will ask you for activities and as soon as you click on “all activities2 the button is finally removed.
Removin an application from the taskmanager works but it has a wrong description. It seemed to be a general issue also appears on OpenSuSE Tumbleweed.