"We are aware of downloading issues when using Firefox 36.

We have been working for months on a 100% new version which works on Firefox 36+ (it does not work on Firefox 35 and below) and we just released a first test version. If you want to test this version and provide feeback on it, please follow this link.

Please stay tuned by following us on Twitter (@downloadhelper), Google + or Facebook."

Firefox has the lead - when Firefox is updated it is incumbent that the add-on developers update their add-on as necessary to keep it fully functional in Firefox. Most all Firefox add-ons are made by a 3rd party; a person could count the number of Mozilla-made add-ons over the past 10 years on one hand, and have fingers left over. Mozilla provides a Rapid Release schedule - https://wiki.mozilla.org/RapidRelease/Calendar - that covers all of 2015, thru the Firefox 43 release on 12-15, so no add-on developer should be caught by surprise when Mozilla releases each new version every 6 weeks. Plus the pre-release development versions - Night, Developer Edition, and Beta are available for anyone who wants to test their add-on against what is coming in the future version releases. That said, the Video DownloadHelper developers are fully aware that there is an issue with their add-on in Firefox 36. https://addons.mozilla.org/en-US/firefox/addon/video-downloadhelper/ ''At the end of the '''About this Add-on''' section.'' "We are aware of downloading issues when using Firefox 36. We have been working for months on a 100% new version which works on Firefox 36+ (it does not work on Firefox 35 and below) and we just released a first test version. If you want to test this version and provide feeback on it, please [https://groups.google.com/forum/#!forum/video-downloadhelper-5 follow this link]. Please stay tuned by following us on Twitter (@downloadhelper), Google + or Facebook."