Who is Populating data/appdata_*/preview?

NC version 29.0.2
PHP version 8.2.19
Postgres version 13.14
Linux 5.10.0-29-amd64 x86_64
Apache version unknown, but I think it’s up to date

I had more than a million files in data/appdata_*/preview. So I have removed them entirely. And, additionally, I have set in config/config.php:

'enable_previews' => false,

But nevertheless, someone has repopulated data/appdata_*/preview again with almost a million files. But in fact, these “files” are not files but a lot of directories with subdirectories names 0-9 and a-f, each contains appr. 64k subdirectories.

Yesterday I have removed all data from within preview again. But already today in the morning I have found in preview a directory b with subdirectories d/2/f/4/7/1/2760010 with no data within any of these directories.

What is there going (wr)on(g)?

See [Bug]: Disabling the preview does not stop the creation of the folder tree · Issue #45697 · nextcloud/server · GitHub