allow Enter on band plan input

band-plan.html

@@ -36,6 +36,12 @@ div#togglebuttons>button {
 
 		document.addEventListener('DOMContentLoaded', () => {
 			update_plan();
+
+			document.getElementById("sel_plan").addEventListener("keydown", (event) => {
+				if (event.key === 'Enter') {
+					update_plan()
+				}
+			});
 		});
 
 		// eslint-disable-next-line no-unused-vars