That's possible, please read this article: [[How to change or reset your Mozilla account password]]. <blockquote>If you reset your account password with a recovery key, you keep access to encrypted sync data (like bookmarks, passwords and settings) on Mozilla’s servers. The recovery key keeps this data connected to your account. Without the recovery key, this synced data is erased for security. However, if you reset your password on a device that has a local copy of your data, signing in with your new password will re-upload the local data to Sync. On a device without local data, the synced data will be permanently lost. </blockquote> To recover your bookmarks, please read [[Restore bookmarks from backup or move them to another computer]]