Ensures the Mac doesn't show the 'Insert...' option for machines that can't accept an insertion.

OSBindings/Mac/Clock Signal/Documents/MachineDocument.swift

@@ -301,6 +301,7 @@ class MachineDocument:
 			switch item.action {
 				case #selector(self.useKeyboardAsKeyboard):
 					if machine == nil || !machine.hasKeyboard {
+						menuItem.state = .off
 						return false
 					}
 
@@ -309,6 +310,7 @@ class MachineDocument:
 
 				case #selector(self.useKeyboardAsJoystick):
 					if machine == nil || !machine.hasJoystick {
+						menuItem.state = .off
 						return false
 					}
 
@@ -318,6 +320,9 @@ class MachineDocument:
 				case #selector(self.showActivity(_:)):
 					return self.activityPanel != nil
 
+				case #selector(self.insertMedia(_:)):
+					return self.machine != nil && self.machine.canInsertMedia
+
 				default: break
 			}
 		}

OSBindings/Mac/Clock Signal/Machine/CSMachine.h

@@ -39,6 +39,7 @@ typedef NS_ENUM(NSInteger, CSMachineKeyboardInputMode) {
 @interface CSMachine : NSObject
 
 - (nonnull instancetype)init NS_UNAVAILABLE;
+
 /*!
 	Initialises an instance of CSMachine.
 
@@ -70,6 +71,8 @@ typedef NS_ENUM(NSInteger, CSMachineKeyboardInputMode) {
 @property (nonatomic, assign) CSMachineVideoSignal videoSignal;
 @property (nonatomic, assign) BOOL useAutomaticTapeMotorControl;
 
+@property (nonatomic, readonly) BOOL canInsertMedia;
+
 - (bool)supportsVideoSignal:(CSMachineVideoSignal)videoSignal;
 
 // Input control.

OSBindings/Mac/Clock Signal/Machine/CSMachine.mm

@@ -516,6 +516,10 @@ struct ActivityObserver: public Activity::Observer {
 	return [[NSString stringWithUTF8String:name.c_str()] lowercaseString];
 }
 
+- (BOOL)canInsertMedia {
+	return !!_machine->media_target();
+}
+
 #pragma mark - Special machines
 
 - (CSAtari2600 *)atari2600 {