In addition to the previously mentioned issues with the rendered view in Cycles under 2.91:
Is anyone else having issues with Cycles sometimes using the Render denoising sample settting for the viewport Denoising sample settings?
Is anyone else having issues with every new Pricipled BSDF material created having emission strength set to one?
So far, aside from one response by Stan Pancakes advising me of a known AMD GPU issue, which does not apply to my hardware, I’ve not had much response about any of these issues.
The render viewport isssues I have been having completely break my lighting and texturing workflow.
Right now, it’s looking as if 2.91 is a hot mess, and I may have to roll back to 2.90, which I would rather not do. I’ve been eagerly awaiting some of 2.91’s new features, but until an unless these problems are solved, 2.91 is simply not very usable.