I repeatedly experienced a problem where Photoshop (2021, latest update running von Mac OS Big Sur, both intel and silicon) saves a file with all layers reduced to one (not background). At first I thought it was my mistake, but it has occured to me several times on two different Machines.
Do you save PDFs from your files ever?
normaly I do not save PDFs from Photoshop.
Is your idea that the last used setting for file saving might have been "photoshop pdf"?
I can never be 100% sure but I think it is pretty unlikely, since I worked on several .psd files, also created some new ones and had this problem only with a few files.
What kind of file format are you trying to save? PSD, TIFF, etc...
Hi Michael, just PSD
Please share a screenshot of your Save As window.
Guten tag, can you show us the contents of Kopie Speichern?
It seems that the settings applied there once are applied for further saves.
Hi, could you show the same window, when saving a document with a layer in addition of the background?