/[\p{Mn}\p{Me}]+/
\p{Mn} or \p{Non_Spacing_Mark}: a character intended to be combined with another character without taking up extra space (e.g. accents, umlauts, etc.).
\p{Me} or \p{Enclosing_Mark}: a character that encloses the character is is combined with (circle, square, keycap, etc.).