Thread:Extension talk:CategoryTree/Problem loading data. Please wait a moment and try again.

Hello

In my site, click all [+] wil show this errom: Problem loading data.Please wait a moment and try again.

No matter in category page or Special:Categories page.

Here is the version info for my site:

CategoryTree-master-2fadcdc

MediaWiki 1.20.0

PHP 	5.3.16

MySQL 5.1.66

Thank you!