This plugin was broken by an upgrade to core on or about November 18, 2020. The client for whom it was developed no longer uses it. If you have need to use it and have a budget, please contact me. PRs will be considered and accepted as quickly as feasible.
TopicDefaultTag is was a plugin to have tags (even staff-only tags) automatically added to topics in a category.
Follow Install a Plugin
how-to from the official Discourse Meta, using git clone https://github.com/pfaffman/discourse-topic-default-tag.git
as the plugin command.
To use, add a default tag in the category settings.
If you have issues or suggestions for the plugin, please bring them up on support.literatecomputing.com.