There seems to be an issue with new extensions policy in Firefox,
Apparently the don’t allow an extension to work if it’s not signed and attached to their oficial site,
Is a new release of the extension, able to be installed, gonna be performed?
@MORANPA It seems this is an issue with Firefox release. See the link below.
Thanks a lot for answering so early,
After manually installing the study as an extension
(I was unable to check the checkbox in my browser)
It wasn’t working, so I had found this solution as well,
I paste the URL in case someone in need of solving same issue,
Thanks a lot!!