Hi and welcome to devnet, QAbstractScrollArea might be a starting point if you want to go from scratch. QTextEdit could also be an inspiration. Take into account that "infinite" means also extensive use of memory so you should have something that unloads useless stuff when not shown as otherwise it's going to eat your system's resources.

@jsulm said in QT Notepad tutorial: @SeanR Isn't the application menu on the top bar in MacOS and not in the application window itself? Good call. I being mostly a MacDev noob and tired failed to look up there. Ty, I was expecting to see on the application. Minus 50 dragon kill points for me...