Hi!
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This is not a Windows bug; it is a combination of the keyboard and the Windows 11 shortcut settings.
The right Alt on many laptops is actually the AltGr (Alternate Graphic) button rather than the regular Alt button on the left side of the keyboard. The right Alt + Shift may cause Windows to recognize it as the Ctrl + Alt + Shift combination, which does not actually work for language changing.
Here is a description of a way on how to test this:
Press Win + Ctrl + O
Press the right Alt button
- Look at the On-Screen Keyboard
- If the Ctrl and Alt buttons are highlighted together, then it is the AltGr button.