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CloseReview for HashColouredTabs+ by Scree
Rated 4 out of 5 stars
Ah OK, I now see the older 0.4.23 version in the old versions section can be installed on 3.6.6 again. So it's there folks, "View all versions" link near bottom of the addon page.
One star off for the inconvenience and confusion. lol
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