TW / Firefox - can't upload images to github issues anymore (CORS failure)

All,

   For about the last 90 days or so, I haven't been able to upload 
images when filing github issues to projects that request screenshots as 
part of the new-issue process.

   I originally just chocked it up to a github problem and didn't take 
the time to look further into it. Now, after about the 8th issue I can't 
include a screenshot to, I did search and try and find an answer, no luck.

   So I brought up the FF developer tools to look for errors, and I do 
get errors like:

Cross-Origin Request Blocked: The Same Origin Policy disallows reading 
the remote resource at 
https://github-production-user-asset-6210df.s3.amazonaws.com/. (Reason: 
CORS request did not succeed). Status code: (null).

Uncaught AttachmentUploadError: App assets attachment upload failed: 
storage request.
     o attachment-upload.ts:63
     setTimeout handler*o attachment-upload.ts:62
     process attachment-upload.ts:104
     d batch-upload.ts:59
     819435 file-attachment.ts:36
     m index.js:96
     attach index.js:164
     p index.js:246
Caused by: error { isTrusted: true, lengthComputable: false, loaded: 0, 
total: 0, eventPhase: 0, bubbles: false, cancelable: false, returnValue: 
true, defaultPrevented: false, composed: false }
attachment-upload.ts:63:35

Cross-Origin Request Blocked: The Same Origin Policy disallows reading 
the remote resource at https://api.github.com/_private/browser/errors. 
(Reason: CORS request did not succeed). Status code: (null).

   I tried disabling the tracker protection, no help. Does anybody know 
what setting in FF is causing this? Github is no help with its chatbot 
assessment other than to say, the browser wasn't able to send the file 
due to a CORS issue.

   I've tried creating exceptions for github.com and zendesk.github.com 
(what the chatbot said was used for upload), but no help either.

   I haven't yet disabled the ublock origins or noscript, but I'll test 
that, what I'm wondering is if there is some known setting that fixes this?

-- 
David C. Rankin, J.D.,P.E.