I tested with "Download with aria2" and "Download with wget", but assume this is valid for all your addons needing native client:
If in Firefox First Party Isolation is enabled no visible action is taken, the addons appear to be dysfunctional. Luckily, there is an easy workaround: Install the addon First Party Isolation. It will add a button, and by clicking on this one First Party Isolation can be temporarily disabled as well as, of course, after sending the download request to the external download tool it can be reenabled with another click. (The addon toggles the Firefox setting privacy.firstparty.isolate).
Either you add similar code to your addon or at least document this issue.
Eeehm, I definitely could reproduce this some days ago. I do not know what was interfering, but now it worked with active First Party Isolation. So let me close this ticket.
I tested with "Download with aria2" and "Download with wget", but assume this is valid for all your addons needing native client:
If in Firefox First Party Isolation is enabled no visible action is taken, the addons appear to be dysfunctional. Luckily, there is an easy workaround: Install the addon First Party Isolation. It will add a button, and by clicking on this one First Party Isolation can be temporarily disabled as well as, of course, after sending the download request to the external download tool it can be reenabled with another click. (The addon toggles the Firefox setting
privacy.firstparty.isolate
).Either you add similar code to your addon or at least document this issue.