I'm journaling my Elixir learnings in Logseq.
Until today I've accepted the fact that LogSeq doesn't support Elixir syntax highlighting.
But today I came across the "Extensions plus" plugin for Logseq, which - besides some other features - adds syntax highlighting for Elixir:
Make sure to restart Logseq to make the plugin work.
Also, make sure "elixir" is checked in the plugin settings: