Dell desktop running Mint Mate 22. Bookmarks missing about 50% of bootups. Saved bookmarks to both HTML and JSON during an occasion they did appear, when they next were missing attempted to restore them via Library pop-up (Manage bookmarks). I could not determine a path to direct the system to either locally saved file. In Library, selected Restore, which then asks me to choose file, but none of the data fields accepted or acted upon input. re-installed Firefox but same result. Then clicked on the saved HTML file, multiple screens flashed on the display, with multiple items in the tray. The final result was the bookmarks were all displayed as expected, but since the problem has been inconsistent, unknown whether they will display on future bootups.

Wish to have guidance on using the Library pop-up to restore saved bookmarks when they are missing. Perhaps some knowledgeable user could post a step-by-step through the restore process.