Do you see any error messages in the Web Console that look related to this issue?

• "3-bar" menu button or Tools -> Web Developer
• https://developer.mozilla.org/Tools/Web_Console

If you use extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) that can block (wanted) content (e.g. Adblock Plus, NoScript, Flash Block, Ghostery) then always make sure such extensions do not block (wanted) content.

• make sure that your extensions and filters are updated to the latest version

• https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems

I believe the bug fix is in progress based on the info at this link: https://bugzilla.mozilla.org/show_bug.cgi?id=1373327

we either need earthlink directly or an affected customer of theirs to work with us to get this problem fixed, since from the outside it is impossible to say what's causing this...

Thanks, hgunited. If the link has the downgrade back to 53.03, I'll be good, because that was working.

Went to Web Console after trying to send an email; All I had was my own email address, the title "Test", and the body only had "Test." Here are what the different notes stated. An unbalanced tree was written using document.write() causing data from the network to be reparsed. For more information https://developer.mozilla.org/en/Optimizing_Your_Pages_for_Speculative_Parsing rich_composer.jsp:65

The character encoding of a framed document was not declared. The document may appear different if viewed without the document framing it. blank.htm

Use of Mutation Events is deprecated. Use MutationObserver instead. ContentVeil.js:2:4726

The character encoding of a framed document was not declared. The document may appear different if viewed without the document framing it. blank.htm

The character encoding of a framed document was not declared. The document may appear different if viewed without the document framing it. data.html

The character encoding of a framed document was not declared. The document may appear different if viewed without the document framing it.  : rich_composer.jsp:413

I'd be happy to work with you all to fix this. How do I contact you, or vice versa?

However, I'm not a coder and don't have any special software, but I can follow directions. Also, I'm on a Mac with latest OS.

thanks jwinogradoff. could you download an run the mozregression tool like it's explained in the video at https://blog.nightly.mozilla.org/2017/06/07/using-mozregression-on-windows/

what it can do is download various builds from the firefox 54 development cycle and asks you if it contains the problem or not - you feedback that information to the tool after you test it in each build and it will narrow down to the exact change in the code that introduced this bug (this is the so-called pushlog). if can come up with the exact pushlog for this regression and share this with us it would be of great help in getting this on a trajectory for a fix.

oh sorry, started replying before i read that you're on a mac - here are instructions for that OS: https://blog.nightly.mozilla.org/2016/10/11/found-a-regression-in-firefox-give-us-details-with-mozregression/ if anything is unclear there, please feel free to ask!

Will do in a bit, Phillipp. I need to get some work down, so just downgraded to 53.03, which works just fine.

Will get to your request in a few hours. Sorry for the delay.

Okay. Felt badly about waiting so downloaded 54.0 again and took the first step in Terminal, sudo apt install python-pip virtualenvwrapper

but it asked me for a password, and I have no idea what it would be.

sudo apt install python-pip virtualenvwrapper Password: Sorry, try again. Password: Sorry, try again. Password:

the password it's asking for would be the admin password of your machine in order to install the tool - https://support.apple.com/HT202035

another user has just run the mozregression tool and reported the results in the bug. thanks for your willingness to help in any case!

Ahh. Was just coming back to run things. Glad you now have the info you need. I'm going to revert back to 53.03 again until I read that the bug's fixed and 54 is ready to go.

Thanks for the time and responses!

Looks that this is related to this patch (URL with value http://) that landed in Firefox 54: https://www.fxsitecompat.com/en-CA/docs/2017/urls-with-no-host-name-are-now-treated-as-invalid/

cor-el said

Looks that this is related to this patch (URL with value http://) that landed in Firefox 54: https://www.fxsitecompat.com/en-CA/docs/2017/urls-with-no-host-name-are-now-treated-as-invalid/

Perhaps if someone can isolate a problem element in the page a bookmarklet could repair the issue as a temporary workaround.

Just tested it again and the email sent successfully and went through. Also able to forward emails. So the issue has been resolved. Thanks to one and all for advice/assistance.

thanks for your update!

Confirming that the fix is in! Test email sent and received, and also could save to draft folder, which I couldn't in the troubled version.

Thanks to everyone for the time and effort spent working on this issue!

Send button is grey -cannot send email messags