This is cool – I just heard a talk related to this subject from one of the authors, Daniel Genkin, who leads the group [0] that found this vulnerability. Seems like they're doing a lot of really interesting work. The talk I heard was specifically about "iLeakage", another vulnerability they found where an attacker can read another tab's data using something like Spectre.
[0]: https://architecture.fail/
[1]: https://ileakage.com/