@njt64 I have experienced this issue as well, a few times, and it sucks. Really sorry you have had to endure this.
This issue has occurred for Windows users, and has been particularly difficult to reproduce. The team has applied some fixes, but is continuing to address as a high priority.
We have an issue open for this on GitHub. I am going to add your report to it, and will share the link here so you can track progress as the team continues to work toward resolving.
In the meantime, could you please open your browser, enter
about: brave in the URL bar, and copy the about Brave info into a reply on this thread. The info will help the team with reproducing the issue.
Again, sincere apologies that you had to deal with this. I am not sure if you also have either an Android or an iOS device, but our Sync feature is now available for iOS and Desktop (Android is just around the corner). The Sync feature will sync your bookmarks across both devices, which can help between now and when this issue becomes fully resolved. I know it isn’t the same as not having to deal with it to begin with, but may help avoid some pain in case this happens again.