steps to reproduce
- run attached zul with IE11 or chrome
- click the button to open the CKEditor
- maximize the editor with its button on the toolbar
- resize the browser
result
the editor shrinks to a smaller size and doesn't expand as the browser size
debug info
- it happens on ZK 6.5.0 and 7.0.7
workaround
- It's related to the window's position attribute, do not specify it or specify it with left, top or parent will eliminate this issue.
<window position="parent">