This is NO WAY a replacement for DownThemAll!
I've got suggested to install this thing in replacement of DownThemAll!
I know DownThemAll! is no longer supported on Firefox Quantum, but instead of suggesting to install this thing, Mozilla Add-Ons should tell the truth and say there is NO REPLACEMENT available, as no one can make a download manager like DownThemAll! —which supported resuming, mirrors, splitting and merging files from different download sources, bandwidth limiting, etc.—, because Firefox Quantum is no longer as customizable as the classic Firefox was.