Talk:T with stroke

Does anyone know what language(s) this is currently used in/was used in? Or where to find that information? I was expecting to find a single Wikipedia page entry for 'Ŧŧ' with that information, but instead it redirects me to the Bar (diacritic) page. Is this Wikipedia policy to not have individual articles for diacritic letters? And if so, why? Non-diacritic letters have their own single articles, and in many languages diacritic letters are considered individual letters completely separate from their base letters.