@licho Since you asked for the actual utf-8 chars, according to this reddit post:
https://old.reddit.com/r/gog/comments/1txlz7z/hey_gog_wtaf/oq1ydsf/
The first one is from the Banum supplement that allows addition of characters from Cameroon scripts (U+1695E). 𖥞 The second one comes from the Rejang supplement that allows for the addition of various languages from Sumatra (U+A95F) ꥟ and the last two are lowercase Greek Koppa (U+03DF) ϟ
