Help!! With Firefox's recent updates, I am unable to open the MP4 files I created in Camtasia and uploaded to Blackboard. I teach at St. John Fisher College.

Question

The college where I work requests that we use Firefox and I am happy to do so. However, in the past few weeks, MP4 files that have worked fine are no longer working because something in Firefox's very recent updates keeps blocking them! I SO wish I had not downloaded your updates.
At St. John Fisher College we use Blackboard CMS. I created many MP4 instructional video tutorials using Camtasia. Our IT department uploads them to Ensemble, then onto our Blackboard courses. For months the videos worked perfectly in Firefox....but no more.
At this moment, every time I try to open them, I must click on the shield at the top left of the screen and disable the protectors.
Dozens of students are required to use these videos. It will be impossible for me to alert them as to the "workaround" that will allow them to watch the tutorials.
Alas, Firefox, always so sleek and easy to use, has become a burden to me:(

Answer 1

Can you convert the URLs for the MP4s to use HTTPS instead of HTTP? There are a couple of ways:
(1) If the URLs are hard-coded in each page, many manual edits.
(2) If an iframe is inserted by a script, edit the script.
As resources for students in case this can't be done easily/quickly, there is the Firefox support article, and there is an add-on which can temporarily allow Firefox users to disable mixed content blocking. Unfortunately, that is a global setting, not a site-by-site setting.
* [[How does content that isn't secure affect my safety?]]
* [https://addons.mozilla.org/en-US/firefox/addon/toggle-mixed-active-content/ Toggle Mixed Active Content - Add-ons]