Describe the bug | 问题描述
A non-US keyboard layout selected renders some button assignments useless. Using a German keyboard layout, the actions (and the indicated keyboard shortcuts) for back/forward are invalid.

To Reproduce | 如何重现
Select "German" keyboard layout, open Mos, try to assign back or forward action to a mouse button. Open Safari and test the assigned actions.

Expected behavior | 期望结果
Correct action being assigned across keyboard layouts.

Screenshots | 相关截图

Correct action assignment using US layout:

Wrong action assignment using DE layout:

System Info | 系统信息:

• Mouse: Logitech MX Vertical
• OS: macOS 26.1 25B78
• Browser: Safari
• Version: 26.1 (21622.2.11.11.9) / Mos 4.0.0 beta 1201 123826
• Application: Safari

Additional context | 额外说明
Potentially further keyboard layouts and actions affected, specifically tested solely Safari back/forward on DE layout leading to unexpected / buggy behavior.