Bug Report
When a node is renamed or deleted, without checking the checkbox "apply this change to subpages", it's placement in the wiki_tree will be broken.
Demostration(original structure): 
After renaming("Page4" to "Page4_rename"): 
You can see that there is a node "Page4" placed as a child of the root wiki_tree node. This is abnormal. Expected result should be: 
Patch is attached with this bug-report page.
Feature Request
Sorry for using this page for a feature request, I'm just too lazy to re-adjust the diff file :p
The thing is that when there are too many wiki pages under the root of wiki_tree, this theme becomes too slow to use. So a filter is added and only the direct children pages/categories of the root of wiki_tree can be filtered.
Demostration: 
Patch is attached with this bug-report page.
Patch File
Here it is: explorer.diff