And this is exactly why OpenTofu was created, to avoid a non competitive relicensing… which, what do you know, actually happened.
But to take on Linux Foundation seems silly, not sure what their angle is here. It’s not like HashiCorp can bully them.
I mean it’s still possible that someone made a blunder and copied code from after the relicense but it sounds highly unlikely given that the whole point of the fork was in preparation to avoiding the relicense… I have to assume they took extra care not to include anything that wasn’t covered by MPL.
According to the article, they basically copied and pasted code from the earlier version to a new place for some new purpose, which is the same thing Hashicorp did for the same purpose in their new version.
No idea what the actual details are, but that seems pretty likely to be permissible under the first license to me.