AEM6.5 edit dialogue is not opening in author
Hi I have dialogue with 3 tab panels with large widget collection. When I click on "edit" getting below error

and when I see https://myauthorsite/apps/poratl/components/shop/mycomponent/dialog.overlay.infinity.json , I do see below instead of seeing dialogue details. ["apps/poratl/components/shop/mycomponent/dialog/dialog.9.json","apps/poratl/components/shop/mycomponent/dialog/dialog.8.json","apps/poratl/components/shop/mycomponent/dialog/dialog.7.json","apps/poratl/components/shop/mycomponent/dialog/dialog.6.json","apps/poratl/components/shop/mycomponent/dialog/dialog.5.json","apps/poratl/components/shop/mycomponent/dialog/dialog.4.json","apps/poratl/components/shop/mycomponent/dialog/dialog.3.json","apps/poratl/components/shop/mycomponent/dialog/dialog.2.json","apps/poratl/components/shop/mycomponent/dialog/dialog.1.json","apps/poratl/components/shop/mycomponent/dialog/dialog.0.json"]
I noticed when I delete few of the items in widgetcollection is working fine and here https://myauthorsite/apps/poratl/components/shop/mycomponent/dialog.overlay.infinity.json I see data like and edit dialogue is working fine.

Is there any limit in adding number of nodes in component dialogue ? what could be the issue.
Note: same dialogues is working fine AEM6.1 but issue with AEM6.5
Also it is noticed https://myauthorsite/apps/poratl/components/shop/mycomponent/dialog.overlay.infinity.json is giving "300 Multiple Choices" http status when seen in network. When this request is 200 status , edit dialogue popup is working fine.