On Sat, Feb 08, 2020 at 08:45:25AM -0800, Aaron Jensen wrote:
> 
> Yeah, unfortunately. Are you on Catalina? I can try the build on my
> work machine as well. It's a 2019 MBP 16", so pretty close to my 2017
> at home, but different. A hardware issue seems unlikely...

No, I’m still on Mojave.

Anyway, one last thing to try. I was reading up on how MacVim handled
this same issue, and while their drawing techniques are quite
different, they did find performance problems with CGLayers so
switched to using CGImages. I’ve given that a go and I don’t think
this patch is quite as fast here as the CGLayer one, but it may be
faster for you.

-- 
Alan Third