For users who had issues migrating data from Brave Muon to Brave Core

Hello Community!

On Friday (Dec 7th), we rolled out an update for some people currently using the older code-base (“Muon”) of Brave. The update was live for 2 hours from 12pm - 2pm (PST) and was intended to install the newer Brave (“Brave Core”) and import all of the data from Muon (Bookmarks, History, Saved passwords, Cookies, Stats (blocked count, etc), and Brave Payments).

Planned Migration Process


  1. User is prompted to upgrade in Brave Muon.

  2. When the user hits “Update” or quits Brave, Muon Brave relaunches and installs Brave Core.

  3. After Brave Core installs, it launches in a new window - any browsing data from Muon should automatically be imported into Brave Core

  4. Brave Muon quits and the icon for Brave Muon will be greyed-out. Windows users will have this icon appear on the desktop, labeled “Brave(old)”

  5. Brave Muon - other than the changing icon - should stay exactly the same as before along with any associated data.

We received several reports of users going through this process as intended. However, we also received several reports stating that the upgrade process was not completed successfully. Based on information from user reports and internal testing, the update process is still confusing and incomplete.

Problems in the Process


  1. The update banner looked like a regular update for the Muon browser

  2. Some users data was not imported into Core from Muon during migration process

    • So when the Brave Core window opens and show a clean profile without any of their previous user data, it seems as though the users’ data had been overwritten (it’s still there, more on this below)
  3. For Windows users, the Muon shortcut was changed to grey and relabeled as intended but pointed to Brave Core instead of Muon

    • This fueled the assumption that previous browsing data and bookmarks were erased

These were the three main points of confusion. You can imagine what this may have looked like on the users end:

  1. Notice update in "regular" looking banner
  2. After update, Brave Core is installed and launched separately from Muon ( which would come as a surprise since the NTP notification didn’t display)
  3. Look through new Brave install, notice no user info has been imported (“Where’s my data??”)
  4. Notice the greyed out Muon shortcut ("Oh, I can still access the old browser and my data from here.")
  5. (Windows users) Launch what is assumed (and intended) to be Brave Muon, but instead opens new build with no data in it ("…What?")

It’s easy to see why this was cause for alarm to many users.

However, we can assure you that your data is still there and has not been overwritten. The update process was designed with this in mind. The rest of this post will be used to aid users who can’t find their data, find the executable file to launch Brave Muon, data didn’t import, or any other issues surrounding Muon to Core migration.

Common Issues, Solutions, and Troubleshooting


“The update erased all my bookmarks and data!”

Don’t panic! The update/migration process was intentionally designed to not overwrite or erase any user data. Any time you install a new build of Brave - Release, Beta, Developer, Muon - it creates it’s own associated profile folder (unless a matching folder was already present). So each build stores session/profile data in a folder separate from the other builds. This way, each build can be installed and run in parallel to one another.

Your Brave Muon data is right where you left it. To verify, navigate to one of the following paths based on your OS:
Windows - ~[Your User Profile]\%AppData%\Roaming\brave
macOS - /Users/[Your User Name]/Library/Application Support/brave
Linux - ./config/brave

If there’s “stuff” in this folder - your data is safe. Most of it is contained in Session-Store-1 file found in this folder.

“If my data is still there, why didn’t it import during the update?”

We have an issue with the importer where order of operations and/or specific points of failure would halt the import process. We’re reworking the import function so that, even if it reaches a point of failure when importing some data, it will still run through and attempt to import any remaining data in the list (essentially the checked boxes on the import screen).

Here’s how you can workaround this issue and still manually import your Muon profile data into Brave Core:

  1. Read this brief article describing how to import browsing data into Brave Core, but don’t import just yet.
  2. Before you import, check the boxes for the data you’d like to transfer but ensure that the Bookmarks option is NOT checked.
  3. Click Import when ready

This should import the desired browsing data into Brave Core.

“Great! But what about all my bookmarks?”

We can get those too! All you need to do is:

  1. Launch Brave Muon (Old)
  2. Export your bookmarks - they’ll export as an HTML file
    • Open Main Menu; Bookmarks --> Export Bookmarks...
  3. Return to Brave Core and follow the instructions again in the link above to import browsing data, but this time select Bookmarks HTML File from the drop down menu.
  4. Click Choose File, navigate to where you saved the exported bookmarks file from Muon and select it.

You should now see your bookmarks appear in Brave Core. Check the Bookmarks Manager located in the main menu to confirm.

“I still want to use the Muon browser/I want to export my Muon bookmarks - but the icon changed and opens the new version!”

The icon should have changed to look like this: image
The name should also have changed from Brave to Brave(old).
For Windows users, if this icon launches Brave Core instead:

  1. Navigate to ~[Your User Profile]\%AppData%\local\brave
  2. You should see a folder here labeled app-[version number of last Brave update] (example, app-0.25.213) with a Brave executable inside.
  3. Use this shortcut to launch Brave Muon.

macOS users, if you’re using macOS and the icon on the dock doesn’t seem to have changed:

  1. Unpin the icon from the dock.
  2. The next time Brave Muon opens, the icon should be changed and you can re-pin it to the dock again.

"The new Brave is just Chromium reskinned!"

This is something we’ve had to frequently address since making this transition. While we understand the concern, this is simply not the case. A few key things to remember:

  1. Chromium =/= Chrome - Chrome is Google’s proprietary web browser built on the chromium engine. The Chromium project is an open source project that allows anyone to leverage this underlying engine to create their own product. Several popular browsers use the Chromium engine, including Vivaldi, Opera, Kiwi, Cent, Yandex - even Brave Muon was built using Chromium.

  2. Brave blocks or removes any code that would send data to Google or any other party without your explicit consent - Read this document for more details on what we do to remove Google code.

  3. We’re still early in the development cycle for the new code-base for Brave (Brave Core) and we have some catching up to do. As a company, we’re committed to making this new version of Brave completely our own and there will be progress made before our 1.0 launch.


Hopefully this helps shed some light on the update process and can assist users who had trouble migrating in finding, restoring or importing their data. If you have any further questions or need additional support, please create a new topic and tag me (@Mattches) and I’d be happy to work through any issues you may have.

Useful links:
Update process support document
How to import or export browsing data?
Deviations from Chromium
Comments from Brave Team (Chrome vs Chromium)
@sriram: New version 0.57 feels really bad
@Mattches: Brave, Chromium, Google, and your data
@luke.mulks: How much Google is removed from Brave Beta?

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