I did a simple search and came up with this: https://www.makeuseof.com/tag/how-to-change-the-default-email-program-for-mailto-links/

I never found that article in my searches, thank you. However, after slowly reading it, I saw tips that I had already tried and were not feasible. I looked at mailtowebmails and that is no longer available. I appreciate your help, but I am still looking for an answer.

See this thread for the main instructions for adding a mailto handler to the Firefox "Applications" section.

• /questions/1235002 How to set Outlook live (Hotmail) as the default mailto

Core el, thanks, I did read that before. I do not how to use that information. I am not using Outlook and don't know how to translate that into the online email I use called centurylink.net . I don't know that programming language or even where to go to create such a file. This is so disappointing, I was using a very handy mailto button on my browser and mozilla deletes all the old addons. Wish I could put in a message request to those add on creators to recreate this button. One where you can assign a website link to open as a default mailto. I am sorry that I don't understand enough coding to create one myself or to mess around with Firefox behind the scenes in some tricky way.

You need to replace the Outlook link with the link to the online mail server that you p0osted above,

This is basically about using the command line of the Web Console to rum some JavaScript to register a new handler.

• https://developer.mozilla.org/en-US/docs/Web/API/Navigator/registerProtocolHandler

I'll see what I can do. I found another article about this. I read it before, but am intimidated about the coding. I have never done that before.

https://support.mozilla.org/en-US/questions/1209459

Note that gecko.handlerService.allowRegisterFromDifferentHost mentioned in that thread is no longer supported in Firefox 53+ and can't be used. Best is to make sure that you are on a page from webmail.centurylink.net when you use the navigator.registerProtocolHandler() code.

Thanks for that tip. :)

Somehow, I solved my problem! Every month I clear everything. Today is end of Feb. When I began my sequence, I had an option for this situation. Here is what happened:

Tools/ options/Privacy Security/ clear history/ all boxes checked/ everything/ clear now / click on red x in box

I clicked onto my bookmark direct link to centurylink webmail to begin all of my logins.

A little popup appeared: Add to mailto application - webmail.centurylink.net (or words to that effect) I answered Yes.

Then I wanted to see if it was added. (Yes it was!) Tools/options/General/ applications/ mailto / use Centurylink Webmail

Went to a website (craigslist) that has mailto as a choice and... it worked!

I solved it by accident. :)

Thanks for the help.

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