Win7
KiCad
Application: Pcbnew
Version: Application: Eeschema
Version: (5.99.0-8593-g9f18fee124), release build
With a file created with Version 5, Eeschema launches the Project Rescue Helper. The mouse cursor then turns into a circle which makes it appear that KiCad is hung up. However, either of the two button choices can be clicked and the program will resume.
Note also: the Project Rescue Helper did not appear to have any affect by clicking either of the two buttons.
ON EDIT: Version information updated to today’s nightly. Issue remains.