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SUMMARY

When using alt+tab to change tasks the tab input is also pressed in the last active window, any GTK based application running on Plasma (lastest), like Firefox, Chrome etc. When you Alt-Tab - KWin Task switcher does its thing. The Tab key however “feeds” through to the focus window, meaning that for as many times as you hit tab after pressing Alt-Tab will send a Tab to the focused window.

STEPS TO REPRODUCE
1. Select a given GTK application, Firefox, Chrome, WebStorm IDE, etc.
2. Press ALT+Tab

OBSERVED RESULT
The Tab key is also passed in the last active window, while the task switcher is been displayed.

EXPECTED RESULT
Change to the desired application without the tab been pressed in the last active window in the list.

SOFTWARE/OS VERSIONS
OS: Fedora release 40 (Forty) x86_64
Kernel: 6.9.9-200.fc40.x86_64
Plasma 6.1.3
Qt: 6.7.2
Theme: [Plasma], Breeze-Dark [GTK2], Breeze [GTK3]
Running on Wayland.

ADDITIONAL INFORMATION