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how to set up firefox to use a mailto link to a webmail account (not gmail, or yahoomail, just a custom webmailaccount ...)

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  • Last reply by f.s3

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I want to setup firefox to ask me, or directly to switch to a webmailaccount and start an email, if I use a MAILTO link. I can not setup this, the only add-ons are for gmail or yahoomail , but I can not find a solution for a custom webmail address. On another PC I got a question from firefox if I want to define this link, an on this PC Mailto is working. On my working PC I also want to set up this function, but I can not manage to do it. can anybody help?

Chosen solution

Here is the usual method:

Let's say the compose address is something like:

https://mail.example.com/compose?to=%s

(1) Open your mailbox or another page on mail.example.com

(2) Open Firefox's Web Console in the lower part of the tab below your mailbox. You can do that using either:

  • Ctrl+Shift+k (Mac: Command+Alt+k)
  • "3-bar" menu button > Web Developer > Web Console
  • (menu bar) Tools > Web Developer > Web Console

If you have not used the Web Console before, you need to prime it. Next to the caret (>>) at the bottom of the Web Console, type Date and press Enter. (If there is a Run button above the console, click the run button.)

Firefox usually will ask you to take some action to prove you understand it's dangerous to run scripts from strangers. Complete that task to enable the console.

(3) Select and copy the following line of script (it's all one line):

navigator.registerProtocolHandler('mailto', 'YourLinkHere', 'HandlerNameHere');

(4) In the tab with your mailbox, paste the script next to the caret (>>) at the bottom of the Web Console.

Edit the script with the information you found from the other system. Make sure to keep the single quotation marks around the text strings.

Then press the Enter key to run the script. Or if there is a Run button above the command line, click the run button.

(5) An infobar should open above the page just below the toolbar area asking you to confirm. Click "Add Application". (Example screenshot attached.) You now can close the Web Console by clicking the "X" on its top bar at the right.

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All Replies (5)

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Hi f.s3, please ignore the spam message promoting an unofficial phone number.

Firefox has a standard way that it sends address information (or page title and URL information for Email Link) to webmail sites. The best way to add the new address to the mailto handlers list is from the site itself, if it offers the ability to add it to your browser.

Unfortunately, because each site is different, we would need more information to help you set up the site yourself. In particular, you need to determine the URL for composing a new message. As an example:

https://mail.example.com/compose?to=john@example.com

Then I can give you the half dozen steps to plug that compose URL into Firefox.

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f.s3 said

On another PC I got a question from firefox if I want to define this link, an on this PC Mailto is working.

Probably, Firefox saved that in a file in your profile folder on that PC, called handlers.json, so we could learn from that one.

To see what the compose URL is on the other PC, open the handlers.json file in a Firefox tab. Here's how:

Open your current Firefox profile/settings folder using either

  • "3-bar" menu button > "?" Help > Troubleshooting Information
  • (menu bar) Help > Troubleshooting Information
  • type or paste about:support in the address bar and press Enter

In the first table on the page, on the Profile Folder row, click the "Open Folder" button. This should launch a new window listing various files and folders in Windows/File Explorer.

Position the window so you can see part of the Troubleshooting Page behind it. Drag and drop handlers.json from File Explorer into the tab.

After a moment, Firefox will display a structured view of the data in the file. If you use Find (Ctrl+f) for mailto Firefox should skip down to the relevant section. Here you should find the critical compose URL.

Any luck?

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jscher2000 said

Any luck?

Thank You! This was a clear instruction and I found the handler and the link. how can I enter this link to work with mailto?

Helpful?

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Chosen Solution

Here is the usual method:

Let's say the compose address is something like:

https://mail.example.com/compose?to=%s

(1) Open your mailbox or another page on mail.example.com

(2) Open Firefox's Web Console in the lower part of the tab below your mailbox. You can do that using either:

  • Ctrl+Shift+k (Mac: Command+Alt+k)
  • "3-bar" menu button > Web Developer > Web Console
  • (menu bar) Tools > Web Developer > Web Console

If you have not used the Web Console before, you need to prime it. Next to the caret (>>) at the bottom of the Web Console, type Date and press Enter. (If there is a Run button above the console, click the run button.)

Firefox usually will ask you to take some action to prove you understand it's dangerous to run scripts from strangers. Complete that task to enable the console.

(3) Select and copy the following line of script (it's all one line):

navigator.registerProtocolHandler('mailto', 'YourLinkHere', 'HandlerNameHere');

(4) In the tab with your mailbox, paste the script next to the caret (>>) at the bottom of the Web Console.

Edit the script with the information you found from the other system. Make sure to keep the single quotation marks around the text strings.

Then press the Enter key to run the script. Or if there is a Run button above the command line, click the run button.

(5) An infobar should open above the page just below the toolbar area asking you to confirm. Click "Add Application". (Example screenshot attached.) You now can close the Web Console by clicking the "X" on its top bar at the right.

Success?

Helpful?

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jscher2000 said

Success?

After a little bit of misspelling i finally managed it. Thank You! for this detailed step by step instructions!

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