Source files with uppercase .F77 file extension do not syntax highlight when opened. .F90 works perfectly.
![f77-bug-001](https://user-images.githubusercontent.com/1883220/223439874-e257d5e9-bbef-41...) ![f77-bug-002](https://user-images.githubusercontent.com/1883220/223439908-27e2f558-fc2b-45...) ![f77-bug-003](https://user-images.githubusercontent.com/1883220/223439933-54744f3c-ccb0-48...) ![f77-bug-004](https://user-images.githubusercontent.com/1883220/223439955-59ccbc64-faa3-4c...)