private void processBackground(int startOffset, Color background) {
   if (myBackground == null && background != null && !myDefaultBackground.equals(background)) {
     addTextIfPossible(startOffset);
     myBackground = background;
     builder.addBackground(background);
   } else if (myBackground != null) {
     Color c = background == null ? myDefaultBackground : background;
     if (!myBackground.equals(c)) {
       addTextIfPossible(startOffset);
       builder.addBackground(c);
       myBackground = c;
     }
   }
 }