I have moved to 4.26.1 some days ago and using for production.
Yesterday I started making some materials, during some hours, and in the last 24h my PC has frozen twice during material edition, just when I changed a scalar parameter value, or pressed the Save button (of course it dones’t happen every time I do it, but twice in a day, as commented).
Maybe it’s Unreal, or maybe my PC, but never happened before, so if you have also noticed it, it may be due to the engine. (Oh, DX12 and Ray Tracing enabled).
Thank you an best regards!