Launcher problems

HMCL Crash: .prefWidth : A bound value cannot be set

What the log looks like

java\.lang\.RuntimeException: \.prefWidth : A bound value cannot be set\.

How to fix it

  1. Open HMCL, navigate to Settings -> Update, and update the launcher to the latest stable version where this JavaFX layout bug has been patched.
  2. If the built-in updater fails, download the newest HMCL executable or `.jar` directly from the official HMCL GitHub Releases page (`HMCL-dev/HMCL`) and replace your old launcher file.
  3. If you need to add mods or datapacks immediately without updating, bypass HMCL's built-in manager by downloading the files in your browser and placing them manually into your `.minecraft/mods` or world `datapacks` folder.
LoadersVanilla, Forge, Neoforge, Fabric, Quilt
SeverityBreaks something
CategoryLauncher problems

Check your own log

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