Hi Aian, yes, there was a change on Outlook recently that affects Firefox and Safari. Here are two other recent threads:

• https://support.mozilla.org/questions/1507363
• https://support.mozilla.org/questions/1506895

I filed a bug report with Mozilla yesterday, but it may be some time before Firefox is fixed. Other options include:

(A) Microsoft might roll back the change. Even if they don't care about Firefox users, they might not want to alienate all the Safari users.

(B) You could consider a workaround. For example, I added a patch for this to my Content-Type Fixer extension. In case you want to try it:

https://addons.mozilla.org/firefox/addon/content-type-fixer/

To turn it on, click its hammer button. When you're done with it, click again and choose Stop Listening.

Thank you, jscher2000.

Thank you for your better understanding and response to this. I will also keep an eye on the progress of the bug report.

Hopefully this will permanently fix very soon.