on Firefox and Windows, it's a disaster in addition to what other comments pointed out, on the demo ( https://www.egui.rs/#demo https://www.egui.rs/#demo ) if

on Firefox and Windows, it's a disaster in addition to what other comments pointed out, on the demo ( https://www.egui.rs/#demo https://www.egui.rs/#demo ) if you have a sidebar open, there is an offset of approximately the sidebar's width (though not exactly) between the system's mouse pointer position and the web app