Bug 18266 Turning off lightbulb preference doesn't turn the lights off right away
When you turn off the lightbulb preference, editors with existing lightbulbs continue to show them. Closing and reopening the editors gets rid of them.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/JavaEditorPreferencePage.java
fTextFields.put(textControl, key);
		if (isNumber) {
			fNumberFields.add(textControl);
			textControl.addModifyListener(fNumberFieldListener);
		} else {
			textControl.addModifyListener(fTextFieldListener);
		}
			
		return textControl;
	}
	
	private void addTextFontEditor(Composite parent, String label, String key) {
		
		Composite editorComposite= new Composite(parent, SWT.NONE);
		GridLayout layout= new GridLayout();
		layout.numColumns= 3;
		editorComposite.setLayout(layout);		
		fFontEditor= new WorkbenchChainedTextFontFieldEditor(key, label, editorComposite);
		fFontEditor.setChangeButtonText(JavaUIMessages.getString("JavaEditorPreferencePage.change")); 
				
		GridData gd= new GridData(GridData.HORIZONTAL_ALIGN_FILL);
		gd.horizontalSpan= 2;
		editorComposite.setLayoutData(gd);
	}
	
	private String loadPreviewContentFromFile(String filename) {
		String line;
		String separator= System.getProperty("line.separator"); 
		StringBuffer buffer= new StringBuffer(512);
		BufferedReader reader= null;