for people with a lot of photos or videos, it’s kind of necessary to be able to have thumbnails of files that aren’t currently stored on the local machine. The seafile devs seem to have concluded that the only way to accomplish this was to use .MSIX files for the installer, and then didn’t look any further.
Nextcloud has this feature, and they didn’t have to switch to MSIX files. The relevant registry code can be found in https://github.com/nextcloud/desktop/blob/de27a2ffd723cc06fb71382b423c407b165f706c/src/libsync/vfs/cfapi/cfapiwrapper.cpp
starting on line 414.
Having these thumbnails is really important for usability. I like the performance and speed of Seafile, but it’s borderline unusable without the thumbnails, leaving me stuck with Nextcloud.