polyzen [1] filed a deletion request for firefox-extension-omnisidebar [2]:
Extension no longer exists on AMO and is discontinued. https://github.com/Quicksaver/OmniSidebar#this-add-on-will-not- receive-any-more-updates [1] https://aur.archlinux.org/account/polyzen/ [2] https://aur.archlinux.org/pkgbase/firefox-extension-omnisidebar/
