Enpass Backup Strangeness

I'm in the process of moving to Linux from Windows and I was test to ensure Enpass would work on Linux. I tried restoring a back up from my Windows Enpass to the Linux Enpass and it told me my password wasn't valid. On Windows I have both the password and a key file, but Linux never asked about a key file. Would this be why the password was invalid?

Then, I noticed my most recent backup was only 1kb in size. Looking at previous monthly backups I'm seeing a wide variety of size differences. If anything, the database should be getting larger, not smaller (and certainly not 1kb or even 88kb as seen in the attached image). It is very scary that my backups might be corrupt. I'm glad I caught this before actually needing it!

I just reran the backup and this time the file size was 9,259kb - almost double even the average previous backups.

Has anyone seen the same thing as me? Any suggestions?

EDIT: I re-backed up Enpass on Windows, then reinstalled Enpass on Linux. This time, I was successful in entering the password AND key file (it asked for it this time). I suspect the file I tried to restore was corrupt and that is why the password wasn't accepted and no key file was asked for in my original attempt. Also, I found the reason the 2026-03-01 backup was only 1kb was because my Versacrypt volume was full. The volume being full might be the problem starting on 202601 too, where each successive month the file got smaller maybe due to it running out of space????

EDIT 2: I wrote a Python script to check the backup files to see if valid. The files are zip files (though no zip extension). Within the zip there is a root directory and within it a directory name primary (I suspect that depends on what the individual named their vault). In the root there should be a file named "backup.info". This states whether there is a key file required. Within the primary directory are two files named "vault.json" and "vault.enpassdb". I check for the presence of those 3 files to determine whether the backup was valid or not. 5 files were missing one or more of those files.

Edited March 7Mar 7 by TN_Dude