Do you use the nav bar removal option? Had mine black screen again which is the second time today. If it happens again I'll try to grab some logs, if I can leave my phone that way.
I do - I've had it hidden for several weeks, and never had a black screen until last night, immediately after I changed a kernel setting. Right now, if I root using any kernel including stock, I get the black screen again. Interestingly while on the black screen I can still bring up the power options (press Power + Volume Up). Otherwise holding the power button for 30 seconds also works, but that appears to reboot, not power down, unless I'm just holding it too long, whereas pressing Power+Volume Up and then powering down, I can go into ADB/Fastboot and switch kernels and stuff.
While not rooted, I even changed the setting back that I did immediately before the issue happened, but using rooted CleanSlate or Kirisakura, the problem happens again as soon as it finishes booting. I just remembered I can try either kernel while not rooted, and I should still be able to use the kernel app's settings if I don't get a black screen. Just interesting that right now I get the black screen even on the rooted stock .037 kernel (with proper vendor_dlkm, etc, too). Everything's perfect on stock now, just missing the root stuff, plus probably can't hide the bootloader unlock without being rooted.
The reason I'm not mentioning what I did in a kernel setting immediately before the screen went black is I feel it needs some verification that the setting or the kernel is the problem before rumours start flying. I was using the kernels fine for weeks. I just haven't had time to work on my phone today other than trying some basic things, and I'm happy that it at least works stock.
I'll put the non-rooted custom kernel on when I get a chance and see what happens then.