Firefox extension "unreputable" -- false positive?

[jscher2000]

Hello, why does Avast tell users of my Firefox extension that it is "unreputable", that you strongly recommend that it be removed, and that doing so will improve their browsing experience.

* Extension: https://addons.mozilla.org/firefox/addon/switch-to-previous-active-tab/
* User report: http://forums.mozillazine.org/viewtopic.php?f=38&t=3051007

Is there a suggested point of contact at Avast to resolve this issue?

In case relevant, VirusTotal analysis of the XPI file:

https://www.virustotal.com/gui/file/3566669db105050bef263140d764b8f1c16a03bd93cee05f97efabac0e2041d5/detection