Choose the recovery scope
| Method | Use it for | Check before relying on it |
|---|---|---|
| Bookmark backup | A saved set of bookmarks. | Restore replaces the current set; HTML import is the merge route. |
| Firefox Backup | A broader browser-data backup where available. | Platform/version availability and whether sensitive data was included. |
| Manual profile copy | A local profile copy, including cases where Firefox will not open. | Close Firefox first; do not assume every file is portable between operating systems. |
| Sync | Keeping chosen categories aligned between devices. | Enabled categories and account; do not treat it as an earlier bookmark snapshot. |
Restore bookmarks from backup · Restore browsing data with a backup file · Manually back up and restore profile data · Choose what information to sync
Plan the next step for your data
Bookmark backup and Sync answer different questions
Mozilla warns that restoring a bookmark backup overwrites the current bookmarks. If you need both sets, its documented alternative is HTML import. Preserve today’s set before restoring an older one. The same source explicitly says continuous Sync is not a true bookmark backup service. Restore bookmarks from backup
Sync can share selected categories such as bookmarks, history and passwords. Categories and device capabilities differ; desktop extensions are not synchronized into mobile Firefox. Check what is actually enabled rather than assuming a signed-in account protects every local setting. Choose what information to sync
Save and restore a bookmark snapshot
- Open Bookmarks from Firefox’s menu, then open the bookmark manager.
- In the Library, select all bookmarks and use Import and Backup to create a backup. Save the dated file somewhere you can find independently of the active profile.
- To use a saved set, return to the same menu, choose Restore and select a dated entry or your saved file. Check its date before confirming.
- Afterward, look for several known bookmarks and folders. Check again after a normal restart.
Example: a file saved before you added a new bookmark does not contain that later addition. Keep both states deliberately if you need both; choosing an older snapshot is not a merge.
Make a manual profile copy for broader recovery
- In
about:support, identify the active profile and open its folder. - Completely close Firefox. Copy the whole profile folder into a separate, dated backup location.
- Keep the original and record the Firefox version and operating system used for the copy.
- For a separate restore destination, create and identify the new profile first. Close Firefox again before copying the backed-up contents into that destination. Preserve any existing destination data before replacement.
- Start that destination and verify named bookmarks and the settings you intended to recover.
Mozilla’s manual method includes destination-file replacement and portability limits. Its current recommendation for an ordinary device move is the built-in backup tool where available. Manually back up and restore profile data
Our controlled copy test reopened a separate Windows destination containing two fake bookmarks and a named test preference. The original bookmark database stayed byte-for-byte unchanged. That scope does not certify passwords, every preference, or cross-platform migration.
Combine bookmark sets using an HTML export
Use an HTML export when the goal is to add bookmarks while retaining the destination set. Keep a dated destination backup first, then open the Library’s Import and Backup menu and choose Import Bookmarks from HTML. Select the HTML file and inspect the imported folders. Import bookmarks from an HTML file
Check both a known source bookmark and a destination-only bookmark afterward. Look for duplicates before removing anything. A JSON restore and an HTML import are different actions; renaming a file does not convert its format.
Broader recovery: backup tool or profile copy
Mozilla now documents a built-in Firefox Backup. Availability depends on the version, platform and configuration, so follow the current availability notes if the controls are absent. Sensitive data requires the protected-backup option. Turning off this backup feature deletes its backup file; preserve a needed copy before changing that setting. Restore browsing data with a backup file
For a manual copy, locate the active profile and completely close Firefox before copying the folder. Restoring folder contents can overwrite destination files. Mozilla cautions that full profiles are not always portable across operating systems. Manually back up and restore profile data
If you use the built-in Firefox Backup
First check the availability notes in Mozilla’s backup guide. The controls depend on version, platform and configuration.
- Find the Backup controls in Settings under the account/Sync area and choose where the file is stored.
- If you need sensitive data included, use the protected-backup option and keep its password available independently.
- For restoration, select the existing backup through the restore controls, then inspect the recovered data after Firefox restarts.
Record the file location and last backup state before a reinstall. Disabling this feature deletes its backup file; a daily-updated file also serves a different purpose from a separately preserved older snapshot. Availability and this UI flow are documentation-checked; our experiment used the manual profile and bookmark methods.
Check the destination before replacing anything
| Record | What to establish |
|---|---|
| Source | Which profile or dated file actually contains a known wanted item? |
| Destination | Which currently open profile will receive the data? What must be kept? |
| Method | Does this operation replace state, add items, or have consequences you have not verified? |
| Check | Which source items and destination-only items will you inspect after reopening? |
Keep originals until those checks are complete. If you cannot identify a usable recovery source, preserve the available profiles and files and use the missing-bookmarks investigation. Creating a backup now records the present state; it cannot manufacture an earlier missing item.
Verify what your copy would recover
Use a separate disposable destination for a restore check when the documented method allows it. Write down the backup date, method, intended data and a small sample you expect to find. After restoration, compare the sample and verify which profile is running. A file that exists on disk is useful evidence of a copy, but not evidence that every item has been recovered.
What our controlled Firefox test showed
A two-bookmark export was restored after a third bookmark had been added. Firefox returned to the saved two-bookmark state and the later third bookmark was absent. A separate full-profile copy restored those two bookmarks and a fake-data preference marker while leaving the original bookmark database unchanged.
Automated checks on Windows with the Playwright-patched Firefox 155.0 engine and Mozilla geckodriver. Fresh profiles and fake data only.
The test notes record the method and results. Bookmark export/import used Firefox’s core APIs; menu instructions are documentation-checked. Built-in Backup, Sync accounts, Refresh and safe-mode restarts were outside the experiments.
Sources & scope
Source checks are dated individually below. Interface labels and availability may vary by version and platform. Controlled Windows Firefox experiments are described in this guide and in the linked test notes.
- Restore bookmarks from backup Restoring from backups and Sync · Checked 2026-10-08
- Restore browsing data with a backup file Availability; sensitive data; restoration; disabling backup · Checked 2026-10-08
- Manually back up and restore profile data Manual backup and restoration · Checked 2026-10-07
- Choose what information to sync Information shared across devices · Checked 2026-10-07
- Import bookmarks from an HTML file Import procedure and resulting folders · Checked 2026-10-08
Source review: Firefox Updates Verification Desk, an automated editorial role. Read the AI and verification disclosure.