Bug 366063

Summary:	Window switcher does not start with specific key combination
Product:	[Plasma] kwin	Reporter:	Mikiya Okuno <mikiya.okuno>
Component:	tabbox	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED FIXED
Severity:	normal	CC:	kde.org
Priority:	NOR
Version First Reported In:	5.7.2
Target Milestone:	---
Platform:	Gentoo Packages
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Mikiya Okuno 2016-07-25 00:10:35 UTC

I change LEFT ALT to LEFT CTRL using Xmodmap. I register CTRL+TAB as "walk through window". The key combination LEFT CTRL (originally LEFT ALT) + TAB switches window to the previous one, but it doesn't display window switcher. Although, RIGHT CTRL + TAb displays window switcher properly.

Reproducible: Always

Steps to Reproduce:
1. Use xmodmap to change LEFT ALT to LEFT CTRL.
2. Register CTRL+TAB as "walk through window".
3. Press LEFT CTRL (originally LEFT ALT) + TAB.

Actual Results:  
Switches window to the previous one, but it doesn't display window switcher.

Expected Results:  
Display window switcher.

shell> cat .Xmodmap
clear lock
clear control
clear mod1

keycode 64 = Control_L NoSymbol Control_L
keycode  66 = Control_L NoSymbol Control_L

add mod1 = Alt_L Meta_L
add control = Control_L Control_R

Comment 1 Martin Flöser 2016-08-01 07:20:35 UTC

This sounds like KWin is not able to recognize that the new control key is a modifier. Can you try to use the gui configuration of the keyboard layout whether there is a pre-defined option describing what you want and whether that works?

Comment 2 Mikiya Okuno 2016-09-11 10:26:43 UTC

Hi Martin,

I'm sorry for slow response. Your suspect is right. The problem happens only when layout is changed using xmodmap. It doesn't happen when layout is changed using GUI system settings. For example, "Left Alt as Ctrl, Left Ctrl as Win, Left Win as Alt" doesn't cause a problem. (But there is no suitable configuration for me in GUI system settings thoug... My preference is to just swap Left Alt and Left Ctrol.)

Comment 3 Martin Flöser 2016-09-12 07:06:49 UTC

can you try to restart KWin after changing the keyboard layout through XModmap? Maybe KWin can pick it up on startup. Just do Alt+Space (Krunner) and enter
kwin_x11 --replace

Comment 4 Mikiya Okuno 2016-09-13 07:13:06 UTC

Hi Martin,

The problem continues to happen after restarting KWin. The odd thing is that window focus just switches to the previous window without displaying window switcher. CTRL(changed from ALT)+TAB does something, but it's like unfinished.

Comment 5 kde.org 2021-11-06 17:43:28 UTC

This issue report is quite old. Can you please confirm, that it still persists with KDE 5.23?

Comment 6 Mikiya Okuno 2021-11-10 05:23:45 UTC

Hi Martin,

The problem appears to be solved in my version. I'm using 5.22, but the problem does not happen.

BTW, I have not faced the problem for long time, because I switched my physical keyboard to ErgoDox, which can change the keyboard layout using its firmware ;)

Kind regards,
Mikiya