Hi @VegasBob – this Processing channel on the forum is a good place for desktop IDE questions (about PDE). If you have questions about the p5.js web editor, ask those in p5.js.
While JavaScript mode is quite old (and no longer works with the new desktop IDE), you can either use the p5.js web editor or you can use the p5.js Mode with the desktop PDE, installable from Contributions Manager > Modes. If you have reliable internet access then the p5.js web editor is recommended because it has a more convenient built-in preview.