I'm giving the tool 1 star because there's work behind it.

But it is not a replacement of DownloadThemAll in any imaginable sense. This tool gets messed when you have many tabs opened, it does not provide you with good filtering options, it shows a pathetic progress bar and has a very poor configuration interface.
Firefox Quantum took a direction that left many good add-on modules out of service in an unrecoverable way.

We miss you DownloadThemAll

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