Image rendering

Like the source, the image was expressed on the gantt timeline. However, when I drag the task on the right graph, the image is rendered continuously and the image flickers. Is there a good way?

Hello Seungmin,
Unfortunately, I couldn’t reproduce it:
http://snippet.dhtmlx.com/5/c130e4bec

Please, add your configuration in the snippet above and make sure that the issue is reproduced there.
Then, click on the Share button and send me the link.
Or send me a ready demo with all the necessary Javascript and CSS files so that I can reproduce the issue locally.