HTTPS Mixed Content Warnings


By default Discourse displays part of a page that is linked, via a URL on a single line, and the developers appear to think they have solve the mixed content issue this can cause, however the Quoting for PLANET topic generates mixed content warnings so it clearly isn’t solved.

There are some work arounds for this:

  1. Don’t post non-HTTPS URLs on single lines
  2. Have an admin add a space to the start of any HTTP URL on a single line

Neither of these are ideal, I have posted to the Discourse site about this but since most other threads on this issue are locked I’m not very optimistic there are are answers other than 1. and 2. above…


This is a test of a repost of the first link in this post to see if a local thumbnail is created:


This does appear to be a Discourse bug, I have posted more on this at


So the answer from the Discourse developers is to “submit a pull request to change the behavior if you believe it can be improved”… which is fair enough really, however, having never written a line of Ruby in my life I’m not best positioned to do this…

Anyone else fancy working out how to prevent Discourse generating HTML that causes mixed content issues? I think it was this pull request which added the feature and it would need a check adding to ensure that a og:image URL in a remote web page, for example:

<meta property="og:image" content="" />

Returned an image, rather than a HTML page (as this dose after a redirect), more detail on the thread at