These are all the topics retrieved by the Code For America Index Crawler and their manually associated synonyms.
This is a draft/prototype, check the project repo or the tool documentation or the project documentation if you are interested in learning more or contribute.
This is how items are being classified in the codeforamerica github
This tree is populated from the json returned by the Get Taxonomy API, see more APIs at the Taxonomy API Swagger.
You can display only a subset of data in this page appending a query parameter like ?category=issues
Categorization is still a work in progress, changes needs to be done via PR in the repo and ideally one day with a tool/idea like a graphical editor.
Empty folders are because there is a category in the taxonomy project but we didn't find a good use of it yet.