I recently setup self hosted (docker) with SQLite, Vikunja version v2.2.2. I have been adding content and when I tried to use the facility to add a task and sub task at the same time using shift+enter I receive a red popup message saying internal server error.
The log file confirms this with similar entries for all my attempts:
[vikunja] 2026-04-05T09:05:52.442708491Z time=2026-04-05T09:05:52.442Z level=ERROR component=http remote_ip=192.168.10.210 method=PUT uri=/api/v1/projects/1/tasks status=500 latency=604.483µs err="database is locked"
The first of the two tasks is added but not the second so it looks like the DB still has some lock after the first add that prevents the second. I tried the same on the demo site and it worked fine although that reports version v2.2.2-149-0834d19f instead of plain 2.2.2 and is presumably using a larger database back end.