We’ll be removing the experimental label from this feature and make it “always on” when this pull request is merged:
While there’s plenty more we’d like to do to improve this feature, it’s proven to be valuable for advanced users, for admins who want to create custom links for their community’s sidebar, and as an extension point for custom topic lists for plugins and theme components.
If there are additional requests for improvements to this feature, go ahead and create a new topic and tag it with topic-filter.