Has anyone been able to use Replay Media Catcher with Firefox and going to secure https sites?

As soon as I set RMC to AUTO and try to go to a site that uses https, e.g. https://www.google.com/ or https://www.youtube.com/, the site is blocked in the browser (with a security warning).

I have tried it on 3 different PC with the same results. I am using RMC 6 and have tried several Firefox versions going back several years.

Note: In order to use Firefox at https sites, such as youtube, and download videos in AUTO mode, it is necessary to set the Network Connection to "Use system proxy settings".
If not set to use the Proxy, Firefox can connect fine to https sites, but videos can then not be downloaded using AUTO.

p.s. Internet Explorer and Chrome works fine with https sites.