Thank you for your help.
I have found the answer in this discussion.

https://forum.bpmn.io/t/extension-elements-cleared-when-loading-xml-in-modeler-editor/6702/9?u=jia-bo-wen
Thank you for your help.
I have found the answer in this discussion.

https://forum.bpmn.io/t/extension-elements-cleared-when-loading-xml-in-modeler-editor/6702/9?u=jia-bo-wen