This issue was caused by the image preview not updating when changing to the SVG file type, but this has now been fixed.

This issue is now resolved so it will be closed.

In summary, it seems like SVG exporting may cause multiple issues that need to be looked into.

Now it seems that an exception is generated when I choose "Save" from the file chooser (as compared to when I hit the "Save As" button). Also, I have reproduced the full frame/blank SVG image each time I generated an SVG file.

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at com.jidesoft.swing.FastGradientPainter.createGradientTile(Unknown Source)
at com.jidesoft.swing.FastGradientPainter.drawGradient(Unknown Source)
at com.jidesoft.swing.JideSwingUtilities.fillGradient(Unknown Source)
at com.jidesoft.plaf.office2007.Office2007Painter.fillBackground(Unknown Source)
at com.jidesoft.status.MemoryStatusBarItem$e_.paintComponent(Unknown Source)
at javax.swing.JComponent.printComponent(Unknown Source)
at javax.swing.JComponent.paint(Unknown Source)
at javax.swing.JComponent.print(Unknown Source)
at javax.swing.JComponent.paintChildren(Unknown Source)
at javax.swing.JComponent.printChildren(Unknown Source)
at javax.swing.JComponent.paint(Unknown Source)
at javax.swing.JComponent.print(Unknown Source)
at javax.swing.JComponent.paintChildren(Unknown Source)
at javax.swing.JComponent.printChildren(Unknown Source)
at javax.swing.JComponent.paint(Unknown Source)
at javax.swing.JComponent.print(Unknown Source)
at javax.swing.JComponent.paintChildren(Unknown Source)
at javax.swing.JComponent.printChildren(Unknown Source)
at javax.swing.JComponent.paint(Unknown Source)
at javax.swing.JComponent.print(Unknown Source)
at javax.swing.JComponent.paintChildren(Unknown Source)
at javax.swing.JComponent.printChildren(Unknown Source)
at javax.swing.JComponent.paint(Unknown Source)
at javax.swing.JComponent.print(Unknown Source)
at javax.swing.JComponent.paintChildren(Unknown Source)
at javax.swing.JComponent.printChildren(Unknown Source)
at javax.swing.JComponent.paint(Unknown Source)
at javax.swing.JLayeredPane.paint(Unknown Source)
at javax.swing.JComponent.print(Unknown Source)
at javax.swing.JComponent.paintChildren(Unknown Source)
at javax.swing.JComponent.printChildren(Unknown Source)
at javax.swing.JComponent.paint(Unknown Source)
at javax.swing.JComponent.print(Unknown Source)
at java.awt.GraphicsCallback$PrintCallback.run(Unknown Source)
at sun.awt.SunGraphicsCallback.runOneComponent(Unknown Source)
at sun.awt.SunGraphicsCallback.runComponents(Unknown Source)
at java.awt.Container.print(Unknown Source)
at org.freehep.graphicsio.exportchooser.AbstractExportFileType.exportToFile(AbstractExportFileType.java:253)
at org.freehep.graphicsio.exportchooser.AbstractExportFileType.exportToFile(AbstractExportFileType.java:282)
at com.lorainelab.image.exporter.HeadLessExport.headlessComponentExport(HeadLessExport.java:72)
at com.lorainelab.image.exporter.ExportDialog.completeSaveButtonAction(ExportDialog.java:455)
at com.lorainelab.image.exporter.ExportDialog.lambda$showFileDialog$13(ExportDialog.java:351)
at com.lorainelab.image.exporter.ExportDialog$$Lambda$320/881015904.accept(Unknown Source)
at java.util.Optional.ifPresent(Unknown Source)
at com.lorainelab.image.exporter.ExportDialog.showFileDialog(ExportDialog.java:343)
at com.lorainelab.image.exporter.ExportDialog.saveAsButtonActionPerformed(ExportDialog.java:330)
at com.lorainelab.image.exporter.ExportDialogGui.lambda$addMainPanel$1(ExportDialogGui.java:72)
at com.lorainelab.image.exporter.ExportDialogGui$$Lambda$206/777213329.actionPerformed(Unknown Source)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Window.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$500(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)