1. --use-gl=desktop - seems to be completely broken, default in 85. 2. --use-gl=angle - renders artifacts it tab bar and address bar, default in 87. 3. Mouse pointer changed to ugly default one from X11 when in chromium window. My system is up to date 12-STABLE amd64, Intel Haswell mobile CPU with iGPU HD Graphics 4600. Latest mesa and xorg with intel xorg driver(SNA, DRI2) and drm-fbsd12.0-kmod-4.16.g20201016. Chromium 85 works great.
Switch to modesetting xorg driver + DRI3 + picom + --use-gl=egl or --use-gl=angle fixed graphics issues for me.