PCI bridge autoconfig was unreliable, at least with Mediators, first boot worked, following reboot might not have. (broke few betas ago)
D3D11 mode OSD was not drawn and usually had single frame in wrong position during mode changes.
Wait for blitter option could cause recursive calls (and in worst case crash due to stack overflow) if delayed chipset pipeline callback was active.
Some updates to fast mode drawing. (was accidentally disabled in b17, genlock support fixed, odd to even bitplane collisions (CLXDAT bit 0) supported and some other adjustments)
Second refresh cycle was not processed in RGA pipeline because inactive NTSC STRLONG check incorrectly skipped part of pipeline processing. Whatever copper wrote in previous cycle was not written to Denise custom register causing strange side-effects.
OCS/ECS sprite behind hires bitplane drew bitplane in lores. (Also drew in lores when sprite was on top of bitplane but it was not visible because sprite lores pixel hide both bitplane hires pixels)
ECS Superhires fast mode drawing supported. (Except if display panel is set to lores but that is useless combination anyway)
Virtual mouse driver horizontal movement works again.