Hi @André36678699dyam,
Thank you for reporting this and for sharing the video. I'm sorry you've had to deal with repeated issues, and I understand your frustration.
I wanted to let you know that we've documented this behavior and shared it with the Photoshop engineering team for investigation.
We've identified that the Curves clipping preview behaves differently when the Modern User Interface is enabled, and your findings on both Windows and macOS are helpful.
For now, disabling Modern User Interface under Preferences > Interface is a temporary workaround.
We don't have a confirmed timeline for a fix yet, but we'll follow up here when we have an update.
Thanks again for taking the time to document this!
Best,
Anshul Saini