Engine v1.75.0 has been released.
This Engine is available in the Editor as pre-release. Please test it with your application and report any issues.
We plan to promote this Engine to be the default version used by the Editor on or after Monday, 8 November 2024.
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Patched to Release v1.75.1 · playcanvas/engine · GitHub
This is now available as the default engine in the Editor.
All my materials turned white after updating to 1.75.1 in every project
can you try adding this your editor project url:
?use_local_engine=https://code.playcanvas.com/playcanvas-1.75.1.js
for example this would be the full url:
https://playcanvas.com/editor/scene/2116769?use_local_engine=https://code.playcanvas.com/playcanvas-1.75.1.js
and let us know if this workaround works for you.
We’re working on a proper fix.
nope 
it’s not working for me
Could you try changing ambient color to black on material?
It didn’t help. Yesterday, I made a commit before updating the editor, and a HARD RESET helped restore the materials.
also, please see this post: Black material starting today