Extremely basic stuff. The "course" served more like an overview of what you need to learn than a real course. They covered very basic HTML, very basic CSS, some Bootstrap and skipped over JavaScript straight to React, where they only broadly defined components and the virtual DOM. The labs offer 100% handholding which I personally dislike, and are very laggy. The quizes were pretty straightforward and don't offer much learning value compared to a more practical approach like a project, which there was none.
Conclusion: I got zero value out of it, but I can see it being somewhat useful for a complete beginner, I just think there are better already existing resources out there for that.
Pros: good for a confused beginner to get an overview of the things he needs to learn to become a junior front-end web developer.
Cons: labs were way too easy, simplistic, rudimentary, laggy, and straight up offered the solutions instead of only providing the things you need to do, and only after to get the possibility to check what you've done. There was also no project, we didn't build anything.
Gave it 2 stars because I appreciated the attempt from Meta, but they need to work harder if they want to make a course / specialization worth more than the paper it's printed on. See you in the next one.