Don't allow pasting of certain items or certain inputs.

stop-pasting.js

const stopPasting = event => {
	const data = event.clipboardData.getData('text');
	if (event.target.id === 'passwordConfirmation' || data === 'theUserPassword') {
		return event.preventDefault();
	}
	
	// If it passes all checks you are still free to do other things, like record the pasted
	// Data elsehwere in the app, or change the data with setData()
};

document.addEventListener('paste', stopPasting);