chat box: dropping messages depending on box size instead of total message limit

Sup guys! <a:pika_wave:1149813374029418508> Rn my chat box widget drops old messages depending on the max message limit. So chat will never show more than e.g. 7 messages, so if someone sends a message while there are already 7 in the chat, the oldest one disappears. So what I wanna do is, I want to drop messages depending on the chat box size, not the message limit. Because if you send e.g. 3 long messages, the whole space of the box is already occupied, but the message wont disappear ofc (3<7 lol).