Is this an FEC violation? FB is no longer pretending to be politically neutral. They are now actively banning conservatives and working directly on behalf of the Democrat Party. Are they now a political PAC, and are they registered as such?
That really isn't the argument. The question is, are they a platform provider, or are they a news journal? The difference is in whether they edit or not... There is wiggle room, as they do have the right to ban or delete fractious, untrue, or threatening articles/posts/users... But if there is a pattern of bias, they become journalists which, believe it or not, puts them in a whole different regulatory sphere, and opens them to legal attacks.
Or that's how I hear it... And they are definitely over the line.