I would recommend opening the file in Notepad ++ to verify the file encoding (as a secondary measure for what Firefox is reporting) and then I would also check the file encoding in your Confluence as described in Troubleshooting Character Encodings to insure that Confluence itself is setup correctly as UTF-8 (recommended), as it may not have the correct character encoding set in the environment.
I do hope that information is helpful.
Thanks for your feedback.
Notepad++ confirms the file is in UTF8.
I've run the encoding test in /admin/encodingtestrun.action and everything is ok except the last part: for "Detect whether the file system is mangling the file name when it is saved", I get this result:
The file name has been mangled
More and more people are building their careers with Atlassian, and we want you to be at the front of this wave! Important Dates Start the Certification Prep Course by 2 April 2019 Take your e...
Connect with like-minded Atlassian users at free events near you!Find a group
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no AUG chapters near you at the moment.Start an AUG
You're one step closer to meeting fellow Atlassian users at your local meet up. Learn more about AUGs