topic Re: UTF-8 added when downloading Word documents from Outlook online in Discussions

UTF-8 added when downloading Word documents from Outlook online

CanadianUser — Wed, 23 Apr 2025 17:02:34 GMT

I’ve encountered a very recent issue when downloading attachments via Outlook Web Access (OWA) in Firefox. The downloaded Word documents are being saved with “UTF-8” prefixed to the filename (e.g., UTF-8_example.docx). This doesn’t occur in Chrome or Edge and seems specific to how Firefox handles the Content-Disposition header when served by Outlook Webmail.

It appears to be related to the way filenames are encoded using the filename*= parameter with UTF-8. Firefox may be misinterpreting this or OWA may not be formatting the headers properly.

Re: UTF-8 added when downloading Word documents from Outlook online

siffemcon — Wed, 23 Apr 2025 22:44:45 GMT

Follow https://bugzilla.mozilla.org/show_bug.cgi?id=1961710.

Re: UTF-8 added when downloading Word documents from Outlook online

dheydrick — Thu, 24 Apr 2025 00:05:48 GMT

Is Mozilla planning on fixing this bug anytime soon?

Re: UTF-8 added when downloading Word documents from Outlook online

siffemcon — Thu, 24 Apr 2025 00:31:31 GMT

What is "any time soon"?? The bug was just added two days ago. It will likely take a few weeks for it to land in the release versions.

Re: UTF-8 added when downloading Word documents from Outlook online

dheydrick — Thu, 24 Apr 2025 19:12:31 GMT

Yes, any time soon. Version 137.0.2 dropped on 4/15/25. I'm betting that I'm not the only customer Mozilla is currently pissing off and potentially losing right now. So, my hope is days rather than weeks.

Re: UTF-8 added when downloading Word documents from Outlook online

siffemcon — Thu, 24 Apr 2025 19:46:02 GMT

Sorry to disappoint you, but it's actually an Outlook problem, not FF.

https://bugzilla.mozilla.org/show_bug.cgi?id=1961710#c17

Re: UTF-8 added when downloading Word documents from Outlook online

DJJ — Fri, 25 Apr 2025 19:12:51 GMT

A Microsoft 365 Support Engineer I brought this to the attention of claims that it is a problem for Firefox to fix. I showed her this thread pointing to your analysis....

Re: UTF-8 added when downloading Word documents from Outlook online

siffemcon — Fri, 25 Apr 2025 20:20:24 GMT

Yeah, MS broke it so Moz has to fix it. Not an uncommon occurrence.

Re: UTF-8 added when downloading Word documents from Outlook online

fiache — Tue, 29 Apr 2025 18:47:17 GMT

You know the old adage:

Software: "Its broken! They will fix it in Hardware!"

Hardware: "Its broken! They will fix it in Software!"

Re: UTF-8 added when downloading Word documents from Outlook online

fiache — Tue, 29 Apr 2025 19:04:50 GMT

BTW, Mahalo for the link above, nice explanation.

Only curious thing is what is Chrome and Edge doing that avoids this(checked in Edge, don't have Chrome on this machine)? And why is Mozilla not following suit?

Have a great day.