Rated 5 out of 5 stars

Still the best and easiest to use.
Works perfecly with YouTube etc.
The little "fish" icon can be placed in various places using the extensions Options (and customize toolbar).
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Unfortunately integration with Firefox's Down-them-all (DTA) extension is still broken (since FF44).
But you can still use Unplug to copy the link (from Unplug's dropdown download options). Then just click the + button in DTA Manager (this paste's the link into DTA).

This user has a previous review of this add-on.