If you want to view or edit the HTML file, you can use the specialized Large File Editor to hide the long lines that may hang or crash normal text editors.
1You may have to deal with privacy laws around cookies outside of Scratch.
2Compatibility mode forces projects to run at 30 FPS, like in Scratch 2.0. Turning this off allows the project to run at a higher framerate (usually 60 FPS, depending on the computer screen's refresh rate).