So your smartphone was the only place you use Firefox browser on? Sync isn't made for backups.

1. Check for Local Backups: ◦ If you had previously backed up your smartphone or if your device has a backup feature, you might be able to restore your Firefox data from there. Check your device's backup settings to see if there's a way to recover app data. 2. Look for Firefox Data on Your Device: ◦ Depending on your smartphone's operating system, you might be able to find local data stored by the Firefox app. However, accessing this data can be complex and may require technical knowledge. 3. Contact Mozilla Support: ◦ If you believe there is a way to recover your old account or data, reaching out to Mozilla Support may provide you with additional options or guidance. 4. Start Fresh: ◦ If recovery isn't possible, you may need to start fresh with your new Mozilla account. You can manually recreate your bookmarks and settings as needed. 5. Use Backup Solutions in the Future: ◦ For future reference, consider using additional backup solutions or regularly exporting your bookmarks and settings to avoid data loss.

"5. Use Backup Solutions in the Future: ◦ For future reference, consider using additional backup solutions or regularly exporting your bookmarks and settings to avoid data loss."

Yeah, if the ability to export bookmarks to a HTML file on Firefox for Android was there to begin with, but you have the power to change that, and please do so.