Attempt to fix core startup problems on some systems (GNOME Desktop?) by adding defensiveness to GUI elements.

src/main/java/org/qortal/gui/Gui.java

@@ -47,12 +47,12 @@ public class Gui {
 		this.splashFrame = SplashFrame.getInstance();
 	}
 
-	protected static BufferedImage loadImage(String resourceName) {
+	protected static BufferedImage loadImage(String resourceName) throws IOException {
 		try (InputStream in = Gui.class.getResourceAsStream("/images/" + resourceName)) {
 			return ImageIO.read(in);
 		} catch (IllegalArgumentException | IOException | ServiceConfigurationError e) {
 			LOGGER.warn(String.format("Couldn't locate image resource \"images/%s\"", resourceName));
-			return null;
+			throw new IOException(String.format("Couldn't locate image resource \"images/%s\"", resourceName));
 		}
 	}
 

src/main/java/org/qortal/gui/SplashFrame.java

@@ -1,6 +1,7 @@
 package org.qortal.gui;
 
 import java.awt.*;
+import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;
 import java.awt.image.BufferedImage;
@@ -29,17 +30,22 @@ public class SplashFrame {
 		private JLabel statusLabel;
 
 		public SplashPanel() {
+			try {
 				image = Gui.loadImage(defaultSplash);
 
-			setOpaque(true);
-			setLayout(new BoxLayout(this, BoxLayout.Y_AXIS));
-			setBorder(new EmptyBorder(10, 10, 10, 10));
-			setBackground(Color.BLACK);
-
 				// Add logo
 				JLabel imageLabel = new JLabel(new ImageIcon(image));
 				imageLabel.setSize(new Dimension(300, 300));
 				add(imageLabel);
+			}
+			catch (IOException e) {
+				LOGGER.warn("Unable to load splash panel image");
+			}
+
+			setOpaque(true);
+			setLayout(new BoxLayout(this, BoxLayout.Y_AXIS));
+			setBorder(new EmptyBorder(10, 10, 10, 10));
+			setBackground(Color.BLACK);
 
 			// Add spacing
 			add(Box.createRigidArea(new Dimension(0, 16)));
@@ -75,6 +81,7 @@ public class SplashFrame {
 
 		this.splashDialog = new JFrame();
 
+		try {
 			List<Image> icons = new ArrayList<>();
 			icons.add(Gui.loadImage("icons/icon16.png"));
 			icons.add(Gui.loadImage("icons/qortal_ui_tray_synced.png"));
@@ -84,6 +91,10 @@ public class SplashFrame {
 			icons.add(Gui.loadImage("icons/icon64.png"));
 			icons.add(Gui.loadImage("icons/Qlogo_128.png"));
 			this.splashDialog.setIconImages(icons);
+		}
+		catch (IOException e) {
+			LOGGER.warn("Unable to load splash frame icons");
+		}
 
 		this.splashPanel = new SplashPanel();
 		this.splashDialog.getContentPane().add(this.splashPanel);

src/main/java/org/qortal/gui/SysTray.java

@@ -61,7 +61,13 @@ public class SysTray {
 		this.popupMenu = createJPopupMenu();
 
 		// Build TrayIcon without AWT PopupMenu (which doesn't support Unicode)...
+		try {
 			this.trayIcon = new TrayIcon(Gui.loadImage("icons/qortal_ui_tray_synced.png"), "qortal", null);
+		}
+		catch (IOException e) {
+			LOGGER.warn("Unable to load system tray icon");
+			return;
+		}
 		// ...and attach mouse listener instead so we can use JPopupMenu (which does support Unicode)
 		this.trayIcon.addMouseListener(new MouseAdapter() {
 			@Override