Org-mode offers a variety of different link types ([http], [file], [bibtex], [magit]...). However, they all get the same look defined by the face value for org-link.
Is it possible to e.g. change the background color depending on the type of link? So that http links would have a yellow background and file links a blue one?
Starting from Org-Mode version 9.x.
Thanks to John Kitchin's answer in Fontify broken links in org-mode, I applied different faces for id-links and file-links with a code similar to this:
(defface org-link-id
'((t :foreground "#50fa7b"
:weight bold
:underline t))
"Face for Org-Mode links starting with id:."
:group 'org-faces)
(defface org-link-file
'((t :foreground "#ff5555"
:weight bold
:underline t))
"Face for Org-Mode links starting with file:."
:group 'org-faces)
(org-link-set-parameters
"id"
:face 'org-link-id)
(org-link-set-parameters
"file"
:face 'org-link-file))
I would make this a comment, but I don't have enough rep so here goes:
Check out this function: org-activate-plain-links (in org.el).
You can modify the function around the 'add-text-properties', doing a match on each link using a cond for instance. I have student supervision now, but if you don't succeed in doing this, I'll add more information later.
org-activate-plain-links is a function alias and interactive for ignore, defined in subr.el.gz. This command is obsolete since 9.0; use ignore instead.
Commented
Sep 22, 2021 at 11:27
See https://github.com/jkitchin/org-ref/blob/651d24df5f52bb3f0d31c71ebdb604ce356fe674/org-ref.el#L484
I use that code to change the appearance of links in org-ref using font lock at https://github.com/jkitchin/org-ref/blob/651d24df5f52bb3f0d31c71ebdb604ce356fe674/org-ref.el#L742
