require is not defined being import html code example

Example 1: require is not defined

remove "type": "module" from package.json

Example 2: require not defined in html file

function createAddItemWindow() {

    // Create a new window
    addItemWindown = new BrowserWindow({
        width: 300,
        height: 200,
        title: 'Add Item',

        // The lines below solved the issue
        webPreferences: {
            nodeIntegration: true
        }
})}