does not interrupt downloads in firefox, you have to put the link manually to start downloading

I am using Firefox version 58.0 with uGet version 2.2.0 on Ubuntu 16.04 LTS (fully updated).
Uget is not able to automatically catch the downloads directly from Firefox. If I copy the Download Link, then Uget can download the file.
Please help me to get it working.

Edit: Tried the #43 method. "Download with Uget" is also not working.

I have the same problem, not working on LinuxMint18.02, Firefox 56, Uget2.0.10

Does not interrupt downloads to favor uGet. Context menu entries work.