replace the QStringList with a QSet<QString> as suggested by RAnders00
replace the QStringList with a QSet<QString> as suggested by RAnders00

https://github.com/Chatterino/chatterino2/commit/2d3fb8950e43af5eae767f57186bf5a8d80790fb#r36317456

fourtf/chatterino2,hemirt/chatterino2,hemirt/chatterino2,Cranken/chatterino2,fourtf/chatterino2,fourtf/chatterino2,Cranken/chatterino2,Cranken/chatterino2,Cranken/chatterino2,hemirt/chatterino2,hemirt/chatterino2