https://www.fileformat.info/info/unicode/font/babelstone_han/blockview.htm?block=katakana_phonetic_extensions
Katakana Phonetic Extensions characters supported by the BabelStone Han font
katakana phonetic extensionssupported bycharactersbabelstonehan
https://www.fontstruct.com/gallery/tag/45655/Katakana%20Phonetic%20Extensions
Katakana Phonetic Extensions (Tag) | FontStruct
FontStruct. Build, Share, Download Fonts
katakana phonetic extensionstagfontstruct