Enhancement Request: Better X11 Keystroke Compatibility for Professional Software

The Issue

Unreal Engine submenus don’t register keystrokes on KDE Plasma Wayland, but work fine on both GNOME Wayland and COSMIC Wayland. The only fix requires enabling “Legacy X11 App Support” → “Always,” which creates a security risk by allowing any X11 app to read all keystrokes.

Steps to Reproduce

  1. Download Unreal Engine Linux pre-compiled binaries from Epic Games
  2. Create a project using one of the templates (e.g., Third Person Template)
  3. Open a Blueprint (e.g., the character blueprint)
  4. Right-click in the Event Graph
  5. Try to type inputs in the search box of the context menu

Expected: Text input works normally
Actual on KDE Wayland: No keyboard input is registered in the submenu
Actual on GNOME Wayland: Works correctly
Actual on COSMIC Wayland: Works correctly

The Problem

This creates a security vs functionality dilemma. GNOME and COSMIC handle this scenario without requiring broad keystroke access or additional configuration, suggesting KDE could implement better X11 compatibility fallbacks.

Proposed Enhancement

Could KDE implement more sophisticated compatibility similar to GNOME’s approach? Ideas:

  • Smart detection of legitimate submenu scenarios
  • Enhanced XWayland integration for complex UI hierarchies
  • Optional per-app compatibility modes

Question

Has anyone hit this with professional software other than Unreal Engine? This affects productivity for developers using industry-standard tools that haven’t fully adopted Wayland yet.

Better X11 compatibility would be a significant advantage for KDE in professional environments.

1 Like

This sounds like a bug that should be filed in the KDE Bugzilla. Could you please file it there?