# todo.tag-counts

How many todos carry each tag, for a tag sidebar or filter chips: a list of
`{ tag, count }`, most used first, ties in tag order (code point, via
collections.sort-by, so `b-2`, `b10`, `b2`, not natural-number order).

- With `includeDone` false only open todos count, so the sidebar shows what is
  left to do; a tag whose todos are all done is left out rather than listed
  with a zero.
- A todo counts once per tag, even if its tag list repeats one.
- Tags are counted as stored. todo.item keeps them normalised
  (todo.normalise-tags), so `home` and `#Home` are already one tag.