The Toki Pona script (aka sitelen pona) needs some codepoints for its ideograms. While Toki Pona is not in Unicode, tokiponists have mostly agreed to use the U+F19xx range in the Private Use Area-A. Most fonts rendering sitelen pona uses that. But using PUA is problematic (no character properties, a lot of restrictions on the web, and constant clashes with other fonts [such as the "nerdfonts" for example]).