Zoom out: Keyboard shortcut not working on Windows

[t-hamano]

What problem does this address?

#66400 added a shortcut to toggle zoom out, but the shortcut (Ctrl+Shift+0) for Windows OS may not be working.

I would appreciate it if you could test whether this is a problem only with my environment or a problem with the Windows OS.

@carolinan @alexstine @torounit I assume you are using Windows OS, so I would appreciate it if you could test it.

What is your proposed solution?

If this is a problem on Windows OS, I would like to suggest a different key combination:

Can we use this key as a zoom out shortcut?	Shortcut	Description	Apps where this shortcut is used
✅	Shift + 0 (shift + 0)	It works	https://defkey.com/what-means/shift-0
✅	Alt + 0 (alt + 0)	It works	https://defkey.com/what-means/alt-0
✅	Ctrl + Alt + 0 (primaryAlt + 0)	It works	https://defkey.com/what-means/alt-ctrl-0
✅	Ctrl + Shift + Alt + 0 (secondary + 0)	It works	https://defkey.com/what-means/ctrl-alt-shift-0
❌	Ctrl + 0 (primary + 0)	At least in Chrome and Firefox this combination is not allowed as it is used to reset the browser zoom level.	-
❌	Ctrl + Shift + 0 (primaryShift + 0)	This is the current shortcut, but it may not work as explained in this issue.	-
❌	Shift + Alt + 0 (access + 0)	This combination is not allowed because it converts a heading block into a paragraph block.	-

Screenshots, screen recording, code snippet

In this video, you can see that the key down event (event.key) itself is not fired by the key combination.

• 0: Key down event occurs and evnet.key is 0.
• Shift + 0: Key down event occurs, but evnet.key is the alternate key, ).
• Ctrl + 0: Key down event occurs and evnet.key is 0.
• Shift + Ctrl + 0: Key down event doesn't occur.

8a2d74715234b363b2498a8dd32405ef.mp4

[torounit]

I was able to reproduce the same issue in Firefox and Chrome on Windows.

I checked using https://w3c.github.io/uievents/tools/key-event-viewer.html and it seems that shift + ctrl + 0 does not trigger a keydown event. But keyup fired.

Also, shift + alt + ctrl + 0 / shift + alt + ctrl + [1-9] fires the keydown event.

[torounit]

The problem of ctrl + shift + 0 not working seems to be a frequently observed problem in the Japanese environment of Windows.

https://jp.finalfantasyxiv.com/lodestone/character/8356239/blog/2960768/
https://nj-clucker.com/excel/ctrl-shift-0-not-working/
https://yashihei.hatenablog.com/entry/2019/03/18/235304

[t-hamano]

Thanks for looking into it. To reproduce this issue, I think both of the following conditions must be met:

• IME (Input method editor) is installed on the Windows OS. Whether IME is installed or not seems to depend on the OS language
• The OS shortcut for switching input languages ​​is enabled

Below is an English article that mentions this issue:

Solved - Can't use Ctrl+Shift+0 (Windows has it) | Windows 8 Help Forums

In any case, it is not guaranteed that switching the zoom out mode with the "Ctrl + Shift + 0" shortcut will always work on the Windows OS, so I think we need to assign a different shortcut.