Periodic force quit or wait notice on Linux - GoldenCheetah/GoldenCheetah GitHub Wiki

This has been reported to happen on some Linux systems , likely on cache refresh, if you are using the Gnome desktop environment. As a workaround, set the timeout for mutter to 0 (or to a higher value than the default of 5000ms):

$ gsettings set org.gnome.mutter check-alive-timeout 0

This is the description what that dconf key is doing:
Timeout for check-alive ping
Number of milliseconds a client has to respond to a ping request in order to not be detected as frozen. Using 0 will disable the alive check completely.