Rated 3 out of 5 stars
IH caused a major problem in version 2.8 for those who also use the popular TabMix Plus add-on.
This problem was acknowledged and repaired in version 2.9. But the update to version 2.9.1 brought back the problems from v 2.8.
Again, the first opened tab will no longer close and the page load on the first tab never seems to complete.
I sent an email to IH 3 days ago but have yet to receive a reply in return.
Version 3.0 resolves this issue.