I installed Discourse the other day on a self-hosted server.
When I copy an URL like https://www.ietf.org/ into a post, Discourse automatically turns into a link with the page’s “title” as text, e.g. like IETF | Internet Engineering Task Force.
This does not happen on meta.discourse.org and I prefer it off.
How can I disable this feature?
I think the enable inline onebox on all domains setting is what you’re looking for. 
Keep in mind if you want to reflect the change on existing messages, you will need to rebuild them!
That’s correct… though it should be working here, we didn’t disable it
e.g. https://www.ietf.org/ and https://www.discourse.org/ and https://meta.discourse.org/ and The Long Earth - Wikipedia
or https://www.ietf.org and https://www.discourse.org and https://meta.discourse.org
[1] pry(main)> InlineOneboxer.lookup 'https://www.ietf.org/'
=> {:url=>"https://www.ietf.org/", :title=>"IETF | Internet Engineering Task Force"}
[2] pry(main)> InlineOneboxer.lookup 'https://www.discourse.org/'
=> {:url=>"https://www.discourse.org/",
:title=>"Discourse is the place to build civilized communities | Discourse - Civilized Discussion"}
[3] pry(main)> InlineOneboxer.lookup 'https://en.wikipedia.org/wiki/The_Long_Earth'
=> {:url=>"https://en.wikipedia.org/wiki/The_Long_Earth", :title=>"The Long Earth - Wikipedia"}
EDIT: some experimentation shows that only URLs with a non-blank path component are inline-oneboxed
e.g. https://www.discourse.org vs. https://www.discourse.org/ vs. Discourse pricing | Discourse - Civilized Discussion vs. Discourse pricing | Discourse - Civilized Discussion
e.g. https://www.discourse.org vs. https://www.discourse.org/ vs. https://www.discourse.org/buy vs. https://www.discourse.org/buy/
EDIT: that’s not how it behaved on try 
Ah, thanks! I read “onebox” but ignored “inline” in the settings, thinking that was about the fancy big preview boxes.
I get the same weird behaviour as @supermathie though.
