master_preferences file

[Brandon Johnson]

Hello everyone,

Does anyone have info or a link to documentation on what effects the "master_preferences" file installed here;

C:\Program Files (x86)\Google\Chrome\Application\master_preferences

I help with tech at schools and I've found on one of our student computers, something happened that caused all extensions to be disabled without the ability to re-enable them.

I found when I delete the "master_preferences" and restart Chrome, the extensions are all re-enabled.

Also, is there a way to decode the file?

When opened in notepad the text starts with {"variations_compressed_seed"

End near the end shows "variations_seed_signature"

[Julian Pastarmov]

Hi,

master_preferences which are now known as initial_preferences is a legacy method of preconfiguring the browser before it's first run. It is surprising that it has effect on every start of Chrome unless you are deleting the "User Data" directory on boot or at other regular intervals. From your comment that you see "variations_compressed_seed" in it which isn't one of the advertised uses of this file I can imagine this file is being placed and controlled by some other software (most likely malware on the system) especially if you or the other administrators are not able to confirm that this is intentional. Removing it should be fine as long as you don't rely on any of the configuration it sets. Even if this is the case I would suggest you replace those use cases with proper Enterprise Policies instead.

You can read more about initial preferences here and here.

Find more information about modern ways of managing Chrome Enterprise Policies here.

Best,

Julian