The email is passed from Firefox as I understand it as a mailto" link.

But I just tried to send a link to this page from firefox using the mailto in the page actions you get when you click the ... this is what appeared in Thunderbird.

What is the problem with that? It does not look to me like what you describe though.

Thanks for the reply, Matt. Here is what I got doing the same thing as you did.

I am using a pre release Version 61 browser. I will do some testing on the release version and see if the results change.

Nope, I get the same with 59.0.2

I have asked one of the Firefox support folk to come here and have a look. Hopefully he understands this better than I do.

Thanks again, Matt, I appreciate your help.

Hi erminea, I don't think Firefox's Email Link feature normally duplicates the URL into the subject. What happens with regular mailto links in pages? For example:

mailto:?body=Body%20text&subject=Subject%20Line

mailto:?body=https%3A%2F%2Fsupport.mozilla.org%2Fquestions%2F1212828&subject=Fun%20Reading

jscher2000 said

Hi erminea, I don't think Firefox's Email Link feature normally duplicates the URL into the subject. What happens with regular mailto links in pages? For example: mailto:?body=Body%20text&subject=Subject%20Line mailto:?body=https%3A%2F%2Fsupport.mozilla.org%2Fquestions%2F1212828&subject=Fun%20Reading

Clicking on the links you provided show the following in the Thunderbird subject line:

Subject Line Fun Reading

So those work normally. Hmm... I honestly don't know why the button would suddenly send something different from a mailto link, or why Thunderbird would interpret it differently. Sorry.

Just to throw some more info into the fray - This issue seems to have started after upgrading my Firefox to Quantum. Would that have anything to do with it?

erminea said

Just to throw some more info into the fray - This issue seems to have started after upgrading my Firefox to Quantum. Would that have anything to do with it?

Well, the Quantum name was first used with Firefox 57 in mid-November and I think this is the first report I've seen of this odd behavior. That leads me to think it could be an obscure setting, an add-on, or some unique interaction with Thunderbird. Do you have any extensions in Firefox that could affect email?

You can view, disable, and often remove extensions on the Add-ons page. Either:

• Ctrl+Shift+a (Mac: Command+Shift+a)
• "3-bar" menu button (or Tools menu) > Add-ons
• type or paste about:addons in the address bar and press Enter/Return

In the left column of the Add-ons page, click Extensions.

Then cast a critical eye over the list on the right side. Any extensions Firefox installs for built-in features are hidden from this page, so everything listed here is your choice (and your responsibility) to manage. Anything email related or that you just do not remember installing or why?

And we have a winner!!! For some unknown reason, WebSite-Watcher Integration, an addon I've been using for years, is the culprit. I have no idea why it is adding the url to my email links now, but once I disabled it, the issue was resolved.

Thanks a lot for your help. You pointed me it the right direction when you mentioned possible issues with addons.

Problem Solved - and many, many thanks for your time helping me!