cannot connect to cloud server (Linux)

[mrmazda]

I'm writing this on behalf of a friend who has severely limited vision. He uses a 42" TV screen as a Linux PC display, but is barely able to use it at all. He has a paid subscription to an audio book service on audible.com. It provides 800 number telephone support, but only for Mac, Windows and various phone models. His Audible.com service worked as expected with his older Linux installations that provided Firefox ESR 38 and older. These older Linux installations went out of support, so he upgraded. With the newer installations, only Firefox 50.x and Firefox ESR 45.x are provided. With the newer versions, he can login, but he can no longer play the books that he paid to access. Attempts to do so produce this message in the new window that opens when he tries to play a book: "Problem connecting to server. Please click to try again." Clicking to try again just repeats the error message. The following is a copy and paste from the browser console when he tries to play a book:

Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at
https://fls-na.amazon.com/1/action-impr ... 9237&csm=1.
(Reason: CORS header 'Access-Control-Allow-Origin' does not match '*').
<unknown>
00000000 1.js line 3 > Function:30:1
Cross-Origin Request Blocked: The Same Origin Policy disallows reading the
remote resource at https://fls-na.amazon.com/1/batch/1/OE/. (Reason: CORS
header 'Access-Control-Allow-Origin' does not match '*'). <unknown>
ReferenceError: lpMTagConfig is not defined lib:385:1
Loading mixed (insecure) display
content "http://g-ecx.images-amazon.com/images/G ... 34931_.png"
on a secure page[Learn More]

Is there something I can do in his Firefox configuration or via some extension to enable the playing of subscribed Audible.com books in ESR 45 or 50 as he was able to do in ESR 38?

[DanRaisch]

Is the extension NoScript installed in the Firefox profile your friend is running? If so, try permitting the scripts on that Audible.com page to run through the NoScript menus.

[mrmazda]

He has AdBlock Plus installed, but not NoScript. Does he need AdBlock Plus to permit a script to run? Could something in Ad Block Plus be blocking the book? Might disabling AdBlock Plus be of any use?

I forgot to mention in OP that we tried Chromium and got the same "Problem connecting to server. Please click to try again." message, so I suppose this might be an site design problem limited to Linux users.

[DanRaisch]

Moving this to MozillaZine Tech as the problem appears with both browsers, indicating it is not a Firefox issue per se.

[Grumpus]

Maybe try SafeMode and see if a connection completes.
Have you tried Amazon for an answer?
It might be the player/viewer was something installed by AWS or a membership is not fully recognized.
If you are running AdBlock you might want to see if there is some indication of what is being blocked from the site and allow that if it looks OK.