@wiige We have added a posting and a line to the 4.1 to 4.2 Upgrade Guide:
Posting added:
https://esotericsoftware.com/forum/d/26006-spine-unity-41-to-42-upgrade-guide/3
Line added to top-most posting (below the 3. bullet point):
[*] Replace any occurrances of `SkeletonGraphicRenderTexture.quadRawImage` with `quadMaskableGraphic`, change the type from `RawImage` to `MaskableGraphic`.[/*]
It would be great if you could add it at the Chinese 4.1 to 4.2 Upgrade Guide as well!
In the posting, you could skip the excerpt from the changelog, since we normally don't translate the changelog. It's the block starting with "> * SkeletonGraphicRenderTexture example component: protected RawImage quadRawImage was changed [..]".