This appears to be caused by an advertisement on the website. Installing an advertisement blocking plugin like uBlock will fix this, and make your entire browsing experience cleaner and faster.

Thanks, I think you nailed it.

I'm glad to hear that your problem has been resolved. If you haven't already, please select the answer that solves the problem. This will help other users with similar problems find the solution more easily.

Thank you for contacting Mozilla Support. :)

I have delayed marking this problem as solved as I wanted to see if it completely resolved the problem.

Whilst the main problem, that of the page generating an infinite number of back button identical addresses there are ramifications that preclude me form regarding the problem as being solved, although it is a "work around" of sorts.

The issues remaining are:

I don't think the use of a third party plug-in could ever be regarded as a "ideal solution" - the problem resides in Firefox itself and should be corrected there.

There are side-effects associated with using an ad-blocker. One major problem is that most embedded proprietary videos that are preceded by an ad are blocked in their entirety (excluding YouTube videos). This can be resolved by adding an exception to the page in which the video is embedded but this is tedious at the very least, and over time it has a detrimental effect on the performance of the ad-blocker due to having to parse a long list of exceptions. These exceptions can, of course, be cleared but doing so adds to the general tedium. In addition, and I can't prove this, but I am nearly certain that there is a general performance hit occurring when an ad-blocker is in use - it was for these reasons that I had my ad-blocker disable (removed actually) that ultimately exposed the original problem.

There remains an other problem on the page that I am using to demonstrate the problem in that there is still always 2 identical addresses generated and it is no impossible to use the back button to exit the page in question - this is almost certainly the old web page annoyance of a page redirecting to itself, but it is not at all certain whether it is a standalone problem or related to the original problem.

For these reasons I can't regard the problem as completely "solved"

although the answer is a workaround that definitely improves the situation.