Dear Helen and Mary--
Helen, please, see below what I meant by coloring read vs. unread post links on a single nested threaded forum.
Mary, thanks for the good news!!!! Just before reading your post, I successfully solved the problem (as you may see below) in Moodle 3.7. Here is my solution based on editing a mustache template for the forum discussion threaded post. The file forum_discussion_threaded_post.mustache is located in /moodle/mod/forum/class/templates directory (in Windows, it is \moodle\mod\forum\class\templates folder, of course). It is a rather short script there.
Find and replace:
<a href="{{{urls.viewisolated}}}">{{subject}}</a>
with:
{{#unread}}
<img src="emailUnreadIcon.gif" alt="posting unread">
<a style="color:blue;" href="{{{urls.viewisolated}}}&mark=read">{{subject}}</a>
{{/unread}}
{{^unread}}
<a style="color:purple;" href="{{{urls.viewisolated}}}">{{subject}}</a>
{{/unread}}
As you may see on the snapshot below, I added an icon of unopen envelop in front of unread posts. To do so, you need to place the emailUnreadIcon.gif file (see attached) into the /moodle/mod/forum directory. Also, when a forum participant opens an unread post, it will be automatically marked as read by the script above. You can adjust the colors of the links as it fits your aesthetics. The first four lines of my script are about unread post links the the three last ones describe read post links.
Let me know what you think or if you have questions. I'm looking forward for the July update of Moodle.
Eugene
