Scanned document on Sonoma not modifiable

My usual workflow when I scan a text document is to correct colors and play with contract to reduce their file size. However, since I upgraded to Sonoma, I find that whatever image I scan, to whatever format (tried png and jpeg so far) end up creating files that I am totally unable to save after modification, or save as another name, from the Preview app of macOS. I get this message on Save As: The document “scan.png” could not be saved as “scan-a”. And this when I play with the colors and Save: The document “scan.png” could not be saved. If anyone knows a fix for this, I would be most grateful, as fixing colors of scanned PNG images reduces their size from 20 MiB to between 1 and 2 MiB. It also helps removing scan artifacts by playing with the contrast. There seem to be additional macOS permissions happening here (judging from the @ in the permissions), but I don't know much more. In the _Inspect_ window for the file, I don't see it being _Locked_ and the listed privileges for my user are _Read & Write_.

-rw-r--r--@ 1 adeynack  staff    15M Oct 16 22:37 scan.png
-rw-r--r--  1 adeynack  staff     4B Oct 16 22:40 test.txt

# EDIT / Additional Info ### Software Used The software used for scanning the _Image Capture_, included in _macOS_. ### More Detailed ls The result of ls -lae@ is as following.

total 29904
drwxr-xr-x  5 adeynack  staff       160 Oct 16 22:40 .
drwx------+ 9 adeynack  staff       288 May 22 21:33 ..
 0: group:everyone deny delete
-rw-r--r--@ 1 adeynack  staff      6148 Oct 16 22:41 .DS_Store
	com.apple.FinderInfo	      32
-rw-r--r--@ 1 adeynack  staff  15296080 Oct 16 22:37 scan.png
	com.apple.lastuseddate#PS	      16
	com.apple.metadata:kMDLabel_djebsaob4taaoilt6jtfvis3ne	     121
	com.apple.quarantine	      22
-rw-r--r--  1 adeynack  staff         4 Oct 16 22:40 test.txt

Funny, this quarantine metadata that we see there 🤔. However, even after removing it...

xattr -d com.apple.quarantine scan.png

... I still cannot _Save_ / _Save As_ the file. And the moment I try again to open it in _Preview_ and save it, the quarantine metadata comes back. ### Alternatives Tried The software saves automatically in ~/Pictures/Scan. I tried copying the file over to ~/Downloads and it had the same effect. I tried _Duplicate_-ing the file from _Finder_ and it still had the same behavior.