The judge dismissed a charge of "securities fraud", which claimed that she had defrauded investors in her own company by making false statements to the public.

The jury convicted her of "false statements", obstruction, and conspiracy.

Right, but information available to those with a confidentiality obligation can still be traded on if acquired legally. That's the crucial point. It's not enough for it to be non-public and material, you must also be in breach of a fiduciary duty (or acting in concert with somebody who is). For example, if a Boeing CEO was at a coffee shop discussing an upcoming acquisition at the table next to you, you'd be able to trade on it, even though it was confidential information not available to the general public and obviously material to Boeing's stock price.

IANAL, but if she traded a picosecond after tweeting: no. If she has zillions of followers and traded a year later: yes, because ’the public’ could be aware of the content of the tweet. A judge will have to decide on in-betweens. When doing that they likely will take into account how open Twitter/X is.

> If I saw the tweet and trade is that legal?

Again, IANAL, but I would think so, if she has ‘enough’ followers.