User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:81.0) Gecko/20100101 Firefox/81.0

Steps to reproduce:

Navigate to https://thejaka.com/
Click "Email Thejaka..." on homepage

Actual results:

This URL:

javascript:'%3c%73%63%72%69%70%74%3e%63%6f%6e%73%74%20%54%41%36%49%36%52%4b%37%3d%5c%27%63%6f%6d%2e%74%68%65%6a%61%6b%61%5c%27%3b%6c%6f%63%61%74%69%6f%6e%3d%64%65%63%6f%64%65%55%52%49%43%6f%6d%70%6f%6e%65%6e%74%28%5c%27%30%61%66%31%66%61%33%62%66%63%30%32%63%66%30%32%30%63%66%63%30%35%30%31%66%37%66%61%30%34%66%31%66%30%65%66%65%65%65%64%65%63%65%62%62%35%64%64%65%61%32%36%5c%27%2e%72%65%70%6c%61%63%65%28%2f%5b%5e%5d%5b%5e%5d%2f%67%2c%28%62%2c%6f%29%3d%3e%28%6f%2f%3d%32%2c%62%3d%28%70%61%72%73%65%49%6e%74%28%62%2c%31%36%29%2b%28%6f%2b%54%41%36%49%36%52%4b%37%2e%63%68%61%72%43%6f%64%65%41%74%28%6f%25%54%41%36%49%36%52%4b%37%2e%6c%65%6e%67%74%68%29%29%25%32%35%36%29%25%32%35%36%2c%5c%27%25%5c%27%2b%28%62%3c%31%36%3f%5c%27%30%5c%27%2b%62%2e%74%6f%53%74%72%69%6e%67%28%31%36%29%3a%62%2e%74%6f%53%74%72%69%6e%67%28%31%36%29%29%29%29%29%3c%2f%73%63%72%69%70%74%3e'

opened in new tab, bat wasn't parsed and navigated to.

Expected results:

Redirect to mailto: URL.

This used to work fine in earlier versions of Firefox, including 70.0.

I don't know if this is a feature gone bad, but it's broken the link.

regression range:
https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=204cda7581188cfc8c8ef11dce4680dadf2b43bb&tochange=f2915d3ee5f8705676e4bb643eab54b62246f25f

given that removing target="_blank" from the link fixes the behavior, it's likely from bug 1503681

I'm no expert by any means, so I don't understand anything, but pasting URL into address bar (and filling in javascript:) doesn't work either.

NI-ing baku who is the author of the previous patch.

Hi,

I've tested this using Firefox Nightly version 83.0a1 (2020-09-25) (64-bit), Beta 82.0b2 (64-bit) and Release 81.0 (64-bit) for windows 10 pro and I’m also able to reproduce the issue. Based on this I will mark each respective flag as affected. All other buttons from page are working.

Best,
Clara

Some alternatives (workarounds) that do work (Some of these aren't exactly workarounds for the bug, but show how to open a mailto: link) are explained here: StackOverflow post

The original link that demonstrated the issue has since been changed to work around the bug.

Here's an alternative link to demonstrate the bug: Demo/Test