RED-6965: Null Pointer in invisible text removal

src/main/java/com/iqser/red/pdftronlogic/commons/InvisibleElementRemovalService.java

@@ -253,7 +253,7 @@ public class InvisibleElementRemovalService {
 
         PathData pathData = pathElement.getPathData();
 
-        if (pathData.getOperators().length == 0 && pathData.getPoints().length == 0) {
+        if ((pathData.getOperators().length == 0 && pathData.getPoints().length == 0) || pathElement.getBBox() == null) {
             writer.writeGStateChanges(pathElement);
             return;
         }