Nice, but I wonder if they plan to switch to GPL, or stay with MPL. No mention of that on the website.
(Not a legal advice) AFAIK, they can’t. If you want to switch a license you have to get consent of all contributors or (in case of CLA shit) consent of the owner of the code
The MPL allows for it as far as I can tell, its just fairly complicated since the MPL would still apply at the file-level for all existing files.