Shortcut `Ctrl+Mousewheel` for Zooming in/out not working on linux

[du33169]

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Describe the bug
The Ctrl/Alt+ Mousewheel shortcut for zooming in/out is not working on Linux. The canvas just scrolls as if the modifier key is never pressed.

To Reproduce
Steps to reproduce the behavior:

1. open draw.io editor
2. create an empty file
3. press down and hold Ctrl
4. scroll the mouse wheel
5. the canvas scrolls up and down, instead of zoom in or out

Expected behavior
The canvas zooms in or out

Screenshots
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draw.io version (In the Help->About menu of the draw.io editor):

• draw.io version v29.0.3

Desktop (please complete the following information):

• Manjaro Linux x86_64
• Kernel: 6.18.4-1
• DE: Plasma 6.5.4 X11

Additional context

• Clicking the zoom button works.
• Keyboard shortcut Ctrl + +/- also works.
• Both shortcuts "Ctrl+mousewheel" and "Alt+mousewheel" are not working.
• Both Keys Left_Ctrl/Alt and Right_Ctrl/Alt are not working.
• The issue exists for both Web and Desktop version of draw.io on Linux, including the AppImage version and the version from package manager.

[draw-io-triage-bot]

👋 Thank you for opening this issue!

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Summary: User reports that Ctrl+mousewheel zoom shortcut doesn't work on Linux (both web and desktop versions), causing the canvas to scroll instead of zoom despite other zoom methods working correctly.

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📝 Additional Information Needed

To help us investigate this more effectively, could you please provide:

• Does this issue occur with both Ctrl+mousewheel and Alt+mousewheel, or just one of them?
• Have you tested this in other browsers (if using web version) to see if it's browser-specific?
• Are there any conflicting applications or system settings that might be intercepting the Ctrl+mousewheel combination?
• Does the issue persist if you try the desktop version downloaded from the official site versus any package manager version?

📋 Bug Report Template

**Environment:**
- draw.io version: [e.g., web app / desktop 24.x.x / Confluence plugin]
- Browser (if web): [e.g., Chrome 120, Firefox 121]
- OS: [e.g., Windows 11, macOS 14, Ubuntu 22.04]

**Steps to Reproduce:**
1. Go to ...
2. Click on ...
3. See error

**Expected Behavior:**
What you expected to happen.

**Actual Behavior:**
What actually happened.

**Screenshots/Files:**
If applicable, add screenshots or attach the .drawio file.

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_{🤖 This is an automated response to help with initial triage. A human maintainer will review this issue. If you've provided all the requested information, no further action is needed - we'll get back to you soon!}