Quick answer: Godot 4 export button greyed out with template-version mismatch warning? Templates must exactly match editor version - download from the same release page.
Updated editor; export button is greyed out. Tooltip: Templates for version 4.3.x not installed.
Download matching templates
Editor > Manage Export Templates > Download. Pulls the exact version. Custom templates require manual download.
Pin version in CI
Build script pulls editor and templates from the same release URL. Never mismatches.
Use Custom Templates only when needed
Custom templates are for engine forks. Most projects use default; default auto-installs cleanly.
“Templates are versioned. Editor changes are template changes.”
Make 'templates installed' a CI gate. Build script that fails early on mismatch saves debugging on the build server.