diff --git a/SquirrelInputController.m b/SquirrelInputController.m
index b327af4db..864784444 100644
--- a/SquirrelInputController.m
+++ b/SquirrelInputController.m
@@ -117,6 +117,16 @@ - (BOOL)handleEvent:(NSEvent*)event client:(id)sender
         if (modifiers & OSX_COMMAND_MASK)
           break;
 
+        // ignore certain combinations with Option+X / Alt+X hotkeys. [GitHub Issue #646]
+        const int arrAltSpecialSymbolsRAW[] = {0x32, 0xE, 0x20, 0x22, 0x2D};
+        if (modifiers & OSX_ALT_MASK) {
+          for (int i = 0; i < sizeof(arrAltSpecialSymbolsRAW); i++) {
+            if (arrAltSpecialSymbolsRAW[i] == event.keyCode) {
+              break;
+            }
+          }
+        }
+
         int keyCode = event.keyCode;
         NSString* keyChars = event.charactersIgnoringModifiers;
         if (!isalpha(keyChars.UTF8String[0])) {