diff --git a/public/main.js b/public/main.js
index ed462e3..683bfc8 100644
--- a/public/main.js
+++ b/public/main.js
@@ -6,18 +6,28 @@ document.addEventListener('DOMContentLoaded', function () {
         ac = undefined,
         last = undefined
     document.getElementById('instance').addEventListener('keydown', function (event) {
-        if (event.key && ((event.key.length === 1 && /[a-z0-9.\-*:]/i.test(event.key)) || (event.key === 'Backspace' && event.target.value !== ''))) {
-            last = event.target.value
-        } else if (event.key === 'Backspace' && event.target.value === '') {
-            last = ''
+        if (event.key && !event.ctrlKey && !event.altKey && !event.shiftKey) {
+            if ((event.key.length === 1 && /[a-z0-9.\-*:]/i.test(event.key)) || (event.key === 'Backspace' && event.target.value !== '')) {
+                last = event.target.value
+            } else if (event.key === 'Backspace' && event.target.value === '') {
+                last = ''
+            } else {
+                event.preventDefault()
+                event.stopPropagation()
+            }
         } else {
             event.preventDefault()
             event.stopPropagation()
         }
     })
     document.getElementById('instance').addEventListener('keyup', function (event) {
-        if (event.key && ((event.key.length === 1 && /[a-z0-9.\-*:]/i.test(event.key)) || (event.key === 'Backspace' && last !== ''))) {
-            keypress(event, event.target.value)
+        if (event.key && !event.ctrlKey && !event.altKey && !event.shiftKey) {
+            if ((event.key.length === 1 && /[a-z0-9.\-*:]/i.test(event.key)) || (event.key === 'Backspace' && event.target.value !== '')) {
+                keypress(event, event.target.value)
+            } else {
+                event.preventDefault()
+                event.stopPropagation()
+            }
         } else {
             event.preventDefault()
             event.stopPropagation()