function fileOpen(accept, callBack) {
	const input = document.createElement('input');
	input.type = 'file';
	input.multiple = false;
	input.accept = accept;
	input.onchange = async function() {
		callBack((!input.files?.length) ? null : input.files[0]);
	};
	input.click();
	input.remove();
}
@param {string} accept
@param {BlobCallback} callBack