'defaults write com.google.Chrome PasswordManagerEnabled true' has no effect

'defaults write com.google.Chrome PasswordManagerEnabled' has no effect. Neither the contents of
/Library/Managed Preferences/com.google.Chrome.plist nor that of
/Library/Managed Preferences/<username>/com.google.Chrome.plist change.
And the corresponding Chrome feature "Offer to save passwords" also stays greyed out / disabled.

I also tried to apply defaults directly to the files

/Library/Managed Preferences/com.google.Chrome.plist and
/Library/Managed Preferences/<username>/com.google.Chrome.plist

using the command

sudo defaults write /Library/Managed Preferences/com.google.Chrome.plist PasswordManagerEnabled -bool true,

also without success. Applying the command to the same plist file in the /Library/Preferences/ folder changed the value, but did not activate the password manager in Chrome.

How can I fix this? Or: where else are these settings configured? Or generally, how to I change Managed Preferences?

UPDATE:

I succeeded to edit the plist files under /Library/Managed Preferences/ using Plist Edit Pro. But that was cumbersome, since I needed to change file and folder permissions first (and restrict them again later). Also the changes get overwritten after reboot, so still looking for a nice solution to change Managed Preferences.

Solution 1:

So, to elaborate a little more, the following steps need to be taken:

1. Copy /Library/Managed Preferences/com.google.Chrome.plist to a user-visible directory (e.g. ~/Downloads)
2. Download Plist Edit Pro, open the file, set PasswordManagerEnabled to YES and save the file
3. Copy ~/Downloads/com.google.Chrome.plist back to /Library/Managed Preferences
4. Change the owner of the file sudo chown root:wheel com.google.Chrome.plist
5. Re-read the preference cache defaults read com.google.Chrome
6. Restart Chrome, check that chrome://policy now lists your change correctly (alternatively hit "Reload policies" until it does
7. Profit!