I know I can do this in Unity with compiz. But didn't find a way to do same in KDE. I'm using Ubuntu 14.04 with full kubuntu-desktop installed.
Btw, I noticed an option for inactive window. But I wanted for active window.
I know I can do this in Unity with compiz. But didn't find a way to do same in KDE. I'm using Ubuntu 14.04 with full kubuntu-desktop installed.
Btw, I noticed an option for inactive window. But I wanted for active window.
1) First Go to System Settings → Window Behavior
2) Open Window Behavior, Select Window Actions by again selecting Window Behavior
3) In Inner Window, Titlebar & Frame section, Use the Mouse Wheel action to Change opacity
Here is a transparent window
Click on window actions (top left corner) → More Actions → Special Window Settings
Go to Appearance & Fixes tab: force any transparency you want for active / inactive state.
You can also manage all created rules in single place as with compiz through:
System Settings → Window Behavior → Window Rules
Additional info: https://forum.kde.org/viewtopic.php?f=212&t=98612
Fully transparent windows in Kubuntu 18.04.2:
System settings > Windows Behavior > Windows Actions.
Inactive Inner Window
Inner Window, Titlebar & Frame
Left Button -- change to Increase Opacity Middle Button -- change to Increase Opacity Right Button -- change to Increase Opacity Mouse wheel -- change to Change Opacity
There is an option to the left of these for a key. On my system it is set at Alt. I have just left it at that.
Click Apply.
Done. Now you can click on a window then hold down alt and turn the mouse wheel. The window will now adjust from solid background to fully transparent depending on how much wheel turning you give it.
You can use this action for one or all windows.