I have three separate versions of Firefox, Firefox, Firefox-ESR, and Firefox Nightly. When I have them all open the task manager puts them all together, it also always uses the icon for Firefox-ESR no matter which version I'm using. How can I get Plasma to consider each version of Firefox as a distinct program, and how can I get Plasma to use each version's icon? (I'm using icon only task manager)

I've found that I can right click the program in the task bar and not group them. It seems to stay too. That's half my issue, but it still uses the same icon for all three. I had made separate .desktop files for each program and specified the icon with a full path name and also gave each program a different name. That was in .local/share/applications. I've since also done the same for the .desktop files in /usr/share/applications but so far it still insists on using the same icon and program name. In the menu launcher the correct icons and program names are showing. How can I get the taskbar to use the icons in the .desktop file?