A faux-helpful and frankly dangerous feature of modern mail clients is their insistence that text that happens to look like a URL and not even a full URL! — should be a clickable link.

That is, you meant to merely mention a site in body text:

When browsing ancient reviews the other day…

But the client decides to “helpfully” link to the site when it renders the message:

When browsing ancient reviews the other day…



  • There isn’t even an “https://” in the original text, so you almost certainly did not mean to create a link.
  • Even with the “https://” prepended, it may not be a usable URL (the domain might have expired years ago or never existed).
  • This was in the HTML part of an email, where you should know full well whether you want an <a> tag or not. But the client thinks it knows better.

I wrote a more inflammatory post on this topic several years ago, but today I’ll stay on the positive side: yes, you can disable this behavior in just about every client, with the exception being Samsung Mail for Android.

What brought this back to mind today was a relevant question from a Marketo user. She wanted to send out an email announcing an upcoming domain change. But the new website is under construction, so (quite understandably) she didn’t want the mail client to link to it.

Perfect example of how this “helpful” behavior breaks a key distinction between hypertext (i.e. text that is merely hyperlink-compatible) vs. deliberate hyperlinking.

Anyway, the solution, in all but one case, is to:

  1. (1) Omit the “http://” or “https://”
  2. and
  3. (2) Insert an invisible Word Joiner character (U+2060) before every period.

The result could never be a valid URL — as Unicode formatting chars aren’t allowed in URLs — disabling the feature almost everywhere. Check out an an Everest Validity test of the following HTML:

<title>An Email</title>
And to make matters worse, B.o.B and Will.I.Am.<br/>

Only one offender, Samsung Mail, still insists on linking, having stripped the WJs for no good reason (they’re perfectly valid in HTML in general):



If anyone can figure out how to convince Samsung, I’m all ears!