[Bug] Horizontal scroll trigger fails in Finder and cannot use mouse side buttons

[teziovsky]

Summary | 摘要

Horizontal scroll in Mos fails in Finder, with two related problems that make the feature hard to use:

1. Mouse side buttons cannot be used as the horizontal-scroll trigger. It would be useful to map the usual browser Back / Forward side buttons as the trigger, so vertical wheel movement becomes horizontal scroll while the button is held.
2. The current trigger only works if it is pressed during an already-started scroll. If the trigger (for example Shift) is held first and then the wheel is moved, horizontal scroll does not activate in Finder. The only working sequence is: start scrolling, then press the trigger mid-scroll. That order is unusable in practice.

This only happens in Finder. Logi Options+ handles the trigger correctly: holding it before scrolling, or pressing it while already scrolling, both convert the wheel to horizontal scroll.

Steps to Reproduce | 如何重现

A. Trigger must be pressed after scrolling has already started (Finder)

1. Open Finder in a folder that can scroll both vertically and horizontally (for example a wide list or icon view).
2. Open Mos and set the horizontal-scroll trigger to Shift.
3. Hold Shift first.
4. While still holding Shift, start scrolling the mouse wheel in Finder.
5. Release Shift, start scrolling the wheel in Finder, and then press Shift while the scroll is already in motion.

B. Side buttons cannot be used as the trigger

1. Open Mos horizontal-scroll / trigger settings.
2. Try to assign a mouse side button (Back / Forward, typically buttons 3 and 4) as the trigger.
3. Confirm that only keyboard modifiers can be chosen, not mouse side buttons.

Expected Behavior | 期望结果

• In Finder, holding the trigger before scrolling should immediately convert that wheel movement to horizontal scroll.
• Pressing the trigger while already scrolling should also switch to horizontal scroll.
• Trigger detection should follow the Logi Options+ model: as long as the trigger is held, wheel movement is horizontal. Press order should not matter.
• Mouse side buttons (browser Back / Forward) should be assignable as the horizontal-scroll trigger.

Actual Behavior | 实际结果

• In Finder, if Shift (or another trigger) is already held and then the wheel is moved, the scroll stays vertical. Horizontal scroll does not start.
• Horizontal scroll in Finder only starts if the wheel is already moving and the trigger is pressed during that motion.
• Mouse side buttons cannot be configured as the trigger, so Back / Forward cannot be used to temporarily switch scroll axis.
• This does not appear to affect other apps in the same way — the problem is specific to Finder.

Environment | 环境信息

• Mos version | Mos 版本:
• macOS version | macOS 版本:
• Mac model / chip | 机型 / 芯片:
• Mouse / trackpad model | 鼠标 / 触控板型号: Logitech Lift
• Connection type | 连接方式: USB receiver (2.4 GHz dongle)
• Affected application | 受影响应用: Finder
• Accessibility permission granted | 是否已授予辅助功能权限: Yes
• Other input, mouse, keyboard, or window-management tools | 其他输入、鼠标、键盘或窗口管理工具:

Mos Settings Involved | 涉及的 Mos 设置

• Smooth scrolling | 平滑滚动
• Reverse scrolling | 反转滚动方向
• Per-app settings | 按应用配置
• Button bindings | 按钮绑定
• Open app/script/file action | 打开 App、脚本或文件动作
• Logi device integration | Logi 设备集成
• Updates / Sparkle | 应用更新

Logs, Screenshots, or Recordings | 日志、截图或录屏

Additional Context | 额外说明

This is mainly a Finder-specific usability issue with the horizontal-scroll trigger:

• Requiring “scroll first, then press the trigger” is easy to miss and hard to do reliably.
• Side-button-as-trigger would be a natural one-handed alternative to Shift, especially on mice that already have Back / Forward buttons.
• Other apps do not show the same failure; the broken trigger order / missing horizontal scroll is isolated to Finder.
• Tested with a Logitech Lift connected via the official 2.4 GHz USB receiver.

[burdo3417]

Even if the mouse has horizontal scrolling wheel It does not function in finder when MOS is running