It’s encrypted over Firefox Sync though, regardless of if you set a master password.
The master password is only needed if you don’t have complete physical security (or your machine is hacked)
Curious if OP was more interested in how secure the Sync feature is vs the manager itself. Sync requires trusting that Mozilla aren’t the bad guys.
I’m assuming Discuit is a private company using proprietary software? If that’s the case, may as well just crawl back to Reddit and gently place the boot back on your neck.
The ex-reddit users who choose to not let sociopath scumbags golden shower them can still be found here.