Use the KWin window rules, Active/Inactive opacity
https://userbase.kde.org/KWin_Rules_Window_Attributes#Window_Attributes
Yes, but you need a compositor that will take care of what your windows look like and behave. There is probably a lot that you can change about the configuration of kwin.
Here is an example of what kwin does and its configuration.
This is the KDE "wiki" page were they talk a lot of how to do something and troubleshoot.
Thanks, I've been having a look at the documentation but can't make heads nor tails of it. :/
They seem to be quite out of date.
Kinda. It was just an example. KDE has a lot of that stuff built in, too, I think.
https://docs.kde.org/trunk5/en/kde-workspace/kcontrol/kwintabbox/index.html#visualization
"Flip switch" sounds a lot like what he wants: https://userbase.kde.org/KWin/Gallery
This is what I was looking for. Thank you so much!!!
I had found wmiface
referenced on https://userbase.kde.org/KWin#Script_the_window_manager_from_the_command_line, which looked like what I needed, but it's not available in the arch repos.
I had also looked into writing a kwinscript for this, but the docs at https://techbase.kde.org/Development/Tutorials/KWin/Scripting left a little to be desired and I couldn't get workspace.clientList()
to even recognize that konsole was running.
This works, thank you so much!!