But the same time, it seems like they're using workarounds, attacking the browser etc. I still believe the underlying network remains unbroken.
Planting that seed in your mind was almost certainly one of the goals of this action. Mission accomplished, FBI.
Tor needs to be run from a live CD with an extended-hop circuit and a text only browser. TBB on regular box considered harmful.
We don't know the situation, so we have to assume that some part of the Tor stack is broken. It's likely to be the integrated web browser that's the weekend, but it could easily be higher or lower level.