Reset modifier button's state

[vishesh92]

Description

Fixes #9940

Copilot Generated summary

This pull request enhances the reliability of modifier key handling in the noVNC UI, especially for VMware VMs using a websocket reverse proxy. It introduces logic to ensure all pressed modifier keys are released when the user closes the browser tab or navigates away, preventing stuck keys on the remote VM. The changes are grouped into modifier key management and event handling improvements.

Modifier key management:

• Added a _modifierKeys configuration object to track modifier keys (Shift, Ctrl, Alt, Windows) and their associated keysyms, codes, and button IDs in the UI object.
• Implemented _sendKeyUp, _releaseModifierKey, and _releaseAllModifierKeys methods to send key release events for individual or all modifier keys, updating UI state accordingly.

Event handling improvements:

• Registered beforeunload and pagehide event listeners to trigger modifier key release logic when the user closes the tab or navigates away, ensuring the remote VM does not retain stuck modifier keys.
• Added handleBeforeUnload and handlePageHide methods to execute modifier key release logic on relevant browser events.

Types of changes

• Breaking change (fix or feature that would cause existing functionality to change)
• New feature (non-breaking change which adds functionality)
• Bug fix (non-breaking change which fixes an issue)
• Enhancement (improves an existing feature and functionality)
• Cleanup (Code refactoring and cleanup, that may add test cases)
• Build/CI
• Test (unit or integration test code)

Feature/Enhancement Scale or Bug Severity

Feature/Enhancement Scale

• Major
• Minor

Bug Severity

• BLOCKER
• Critical
• Major
• Minor
• Trivial

Screenshots (if appropriate):

How Has This Been Tested?

How did you try to break this feature and the system with this change?

[Copilot]

Pull request overview

This PR fixes a bug where modifier keys (Shift, Ctrl, Alt, Windows) remain stuck in the pressed state on VMware VMs when the browser tab/window closes unexpectedly, particularly when using a websocket reverse proxy. The solution adds event handlers to detect tab closure and release all pressed modifier keys before the connection is terminated.

Key changes:

• Introduces a centralized _modifierKeys configuration object mapping modifier keys to their keysyms, codes, and button IDs
• Adds beforeunload and pagehide event listeners to detect tab/window closure
• Implements helper methods to release individual or all pressed modifier keys

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 17.56%. Comparing base (4379666) to head (e05b970).
⚠️ Report is 4 commits behind head on 4.22.

Additional details and impacted files

@@             Coverage Diff              @@
##              4.22   #12187       +/-   ##
============================================
+ Coverage     3.58%   17.56%   +13.97%     
- Complexity       0    15548    +15548     
============================================
  Files          445     5910     +5465     
  Lines        37536   529129   +491593     
  Branches      6905    64634    +57729     
============================================
+ Hits          1346    92939    +91593     
- Misses       36024   425732   +389708     
- Partials       166    10458    +10292     

Flag	Coverage Δ
uitests	3.58% <ø> (ø)
unittests	18.63% <ø> (?)

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[vishesh92]

@blueorangutan package

[blueorangutan]

@vishesh92 a [SL] Jenkins job has been kicked to build packages. It will be bundled with KVM, XenServer and VMware SystemVM templates. I'll keep you posted as I make progress.

[blueorangutan]

Packaging result [SF]: ✔️ el8 ✔️ el9 ✔️ el10 ✔️ debian ✔️ suse15. SL-JID 15916

[DaanHoogland]

clgtm, one question.

[DaanHoogland]

clgtm, one question.

also tested ok in lab env