Review for about:addons-memory by FeRDNYC
Rated 4 out of 5 stars
As others have noted, this extension is currently not functional due to a change to the JavaScript functionality in Firefox 44. This was a "breaking change" that was expected to impact many addons, but needed to be done at some point.
Github user @InternalError503 has produced a patch for the breakage in about:addons-memory under Firefox 44+, and submitted it on github. There's no word yet from Nils (the author) about when or if a new version of the addon might be released with this fix, but it's only been a few days:
https://github.com/nmaier/about-addons-memory/pull/23
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