Forgot to mention… if you want to know if the file is a folder before you add the menu item (so it won’t appear on regular files), you can use if (file.children) menu.addItem().... If you want to do additional checks, like whether it already has a folder note, you can, but they have to be synchronous with no async/await. (So you can use e.g. app.vault.getAbstractFileByPath() to test for a file’s existence, but not .exists(), because the former is synchronous and the latter is not.)