I noticed on the Humane Tech discourse (community.humanetech.com) that it is not possible for me to pin topics consistently, either globally or per category. Sometimes the pinned topic stays pinned, but most of the time the topic is immediately unpinned after me pinning it. Also I never managed to get more than one pinned topic in a single category or globally.
Example of topic I’d like to pin: Contribute awesome tech to awesome-humane-tech list on Github - Apps and Tools - Humane Tech Community
I am using Firefox 58 on Ubuntu.