unable to create a diff between two versions in the QGIS plugin

[PatrikMizera]

1. I have created a simple project with 1 survey layer
2. synchronized new version V2. in which I have added 3 new points
3. synchronized new version V3. in which I have updated 1 point (from the previous version), deleted 1 point (from the previous version), added 1 new point
4. I tried to create a difference between these two versions as described in this test

However, after I pressed "run" I got this error

Here is the error in text form:
Traceback (most recent call last):
File "/Users/patrikmizera/Library/Application Support/QGIS/QGIS3/profiles/test01/python/plugins/Mergin/processing/algs/create_diff.py", line 149, in processAlgorithm
features = diff_table_to_features(diff[table_name], db_schema[table_name], fields, fields_mapping, db_conn)
File "/Users/patrikmizera/Library/Application Support/QGIS/QGIS3/profiles/test01/python/plugins/Mergin/diff.py", line 231, in diff_table_to_features
wkb_with_gpkg_hdr = base64.decodebytes(value.encode("ascii"))
AttributeError: 'NoneType' object has no attribute 'encode'

Execution failed after 1.53 seconds

Present in:
dev plugin with dev server
production plugin with production server

Mergin plugin artefact: https://github.com/MerginMaps/qgis-plugin/actions/runs/9482639845
Tested on MAC against app.dev (2024.4.0)

[MarcelGeo]

Issue is occuring also on currently released plugin. Therefore not related to editor implementations.