Different behavior of xobject after upgrading from 14.10.9 to 15.10.8

After upgrading our xwiki-staging env from 14.10.9 to 15.10.8, i noticed that there is an unexpected issue dealing with textareas. Neither the content nor the editor is displayed after upgrade in view- or edit-mode. The configuration of both is the same.

For a better understanding i’ve done some screenshots, so you might see the differences.
xwiki_edit_14109
xwiki_edit_15108
xwiki_object_config
xwiki_view_14109
xwiki_view_15108

Thanks.

I figured out that its on clientside, the complete folder “/xwiki/skins/flamingo/ckeditorplugins” was missing after upgrade.

This folder is definitely not supposed to exist in recent versions of XWiki (ckeditor related resources are located in JAR packages, webjars), so your problem is elsewhere.