Bug 54658 Bug in Code Formatter > Line Wrapping
Code Formatter > Line Wrapping: The preview is not shown correctly from the beginning. The "Set line width for preview window" number has to be reset to another OR even THE SAME value to correct the display.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/formatter/LineWrappingTabPage.java
/**
	 * A special options store wherein the preview line width is kept.
	 */
	protected final Map fPreviewPreferences;
	
	/**
	 * The key for the preview line width.
	 */
	private final String LINE_SPLIT= DefaultCodeFormatterConstants.FORMATTER_LINE_SPLIT;
	
	/**
	 * Create a new line wrapping tab page.
	 */
	public LineWrappingTabPage(ModifyDialog modifyDialog, Map workingValues) {
		super(modifyDialog, workingValues);
		fDialogSettings= JavaPlugin.getDefault().getDialogSettings();
		
		final String previewLineWidth= fDialogSettings.get(PREF_PREVIEW_LINE_WIDTH);
		
		fPreviewPreferences= new HashMap();
		fPreviewPreferences.put(LINE_SPLIT, previewLineWidth != null ? previewLineWidth : Integer.toString(DEFAULT_PREVIEW_WINDOW_LINE_WIDTH));
		
		fCategories= createCategories();
		fCategoryListener= new CategoryListener(fCategories);
		
		fCurrentKey= ((Category)fCategories.iterator().next()).key;
	}
	
	/**