Only modifier states should toggle.

guacamole-common-js/src/main/resources/oskeyboard.js

@@ -243,15 +243,15 @@ Guacamole.OnScreenKeyboard = function(url) {
                     // Set up click handler for key
                     key_element.onclick = function() {
 
-                        // Toggle pressed state
-                        key.pressed = !key.pressed;
-
                         // Get current cap based on modifier state
                         var cap = key.getCap(on_screen_keyboard.modifiers);
 
                         // Update modifier state
                         if (cap.modifier) {
 
+                            // Toggle pressed state
+                            key.pressed = !key.pressed;
+
                             // Construct classname for modifier
                             var modifierClass = "guac-keyboard-modifier-" + cap.modifier;