WindowFix

WindowFix addresses a Windows-specific Minecraft issue where interacting with the title-bar system menu (right-click title bar, minimize, restore, etc.) may cause the game loop to hang or stutter.

Environment

• Windows client

Fix Modes

WindowFix provides two modes via client config:

1. Block native system menu (stability-first)
   Blocks title-bar right-click system menu entirely to avoid entering the Win32 menu modal loop.

2. Native compatibility mode
   Keeps native right-click system menu and enables MNS_MODELESS to reduce blocking likelihood.

Configuration

Config file is generated after first launch:

config/windowfix-client.toml

Example:

blockTitleBarSystemMenu = false
keepActiveDuringSystemMenu = true

Restart the game after changing config values.

• blockTitleBarSystemMenu
  • true: Disable title-bar right-click native system menu.
  • false: Keep native system menu behavior.
• keepActiveDuringSystemMenu
  • Only effective when blockTitleBarSystemMenu = false.
  • true: Suppress transient focus-loss messages during system menu operations to reduce brief hitching.
  • false: Keep default focus behavior.

Usage

1. Put the built JAR into your client mods directory.
2. Launch the game and adjust config/windowfix-client.toml as needed.

Log Keywords

Search these in latest.log:

• Installed Win32 window hook for system menu freeze workaround.
• Enabled MNS_MODELESS on system menu.

Known Limitations

• Windows-only behavior.
• In native compatibility mode, brief hitching may still happen depending on system window management behavior.