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.