The application display the icons on a gray background when download the image

REPRODUCIBILITY LEVEL:
====================
Always
STEPS:
====================
Steps
1.Open the Liferay APP with the Collaboration portlet with user
3.Click on the “Add a Rectangle” icon.
4. Click on the Fill button and select a color.
5. Click on the “Add a Text” icon.
6. Type “Test” and click on the “Save” Button.
8. Click on the “Download” icon.

CURRENT RESULT:
====================
The application display the icons on a gray background when download the image

EXPECTED RESULT:
====================
The application display the icons on a WHITE background when download the image