Fixed user colours not showing on forum posts.

templates/forum/macros.twig

@@ -478,7 +478,7 @@
         {% set author_id = post.user.id %}
         {% set author_name = post.user.name %}
         {% set author_title = post.user.title %}
-        {% set author_colour = post.colour %}
+        {% set author_colour = '--accent-colour:' ~ post.colour %}
         {% set author_country = post.user.countryCode %}
         {% set author_created = post.user.createdTime %}
         {% set author_posts_count = post.postsCount %}