Noooo... To get icons, It refreshes all my bookmarks with bookmarks as login on some online services so now all these accounts have updated last seen time...
Future of FF with Webextensions isn't clear if addons do what they want and can't be controlled by user not vice-versa...

So addon is helpful to locate a bookmark folder, to find folder that contains an specific bookmark

When I click addon button it opens a small, compact window of it's own, how to make that open in a tab instead?