Whenever I'm in a call, the screen turns black but the touchscreen is still working, moving icons, toggling knobs, etc etc
I remember having this in other custom roms since kit kat lol
Fixed that behaviour by installing ggl Phone app from Playstore. Not really the best solution caus the phone app that comes with bliss has call recording included. But temporarily it is okay. If i want to record anything i can reactivate it.