Fix dark-theme and arrow for add-printer-dialog. [CURA-6435]

resources/themes/cura-dark/theme.json

@@ -94,8 +94,8 @@
         "action_button_active": [39, 44, 48, 30],
         "action_button_active_text": [255, 255, 255, 255],
         "action_button_active_border": [255, 255, 255, 100],
-        "action_button_disabled": [39, 44, 48, 255],
-        "action_button_disabled_text": [255, 255, 255, 80],
+        "action_button_disabled": [19, 24, 28, 255],
+        "action_button_disabled_text": [200, 200, 200, 80],
         "action_button_disabled_border": [255, 255, 255, 30],
 
         "scrollbar_background": [39, 44, 48, 0],