I don’t. After discovering that flaw plus the issue I was originally reporting in that thread plus another issue where Joplin deleted all my notes, I just stopped using the software.
I’m reasonably happy using Obsidian now, despite it being closed source and not supporting anything but proprietary sync mechanisms. I have no had any data loss issues with it.
https://discourse.joplinapp.org/t/keep-original-notebook-on-...
I just checked my log.txt file and I can't find mention of my master password. Maybe it is fixed?