Archive Plugin is not working

Hi Guys,

I just started learning Openfire and it seem working for awhile. I started browsing and adding some plugins, i tried to install Monitoring to archive all the conversation, but it seem its not working at all, it is already enable but it did not archive all the conversion, when i tried to press rebuild an error occurred: "TypeError: element.getInlineOpacity is not a function". I don't know the meaning of this error, maybe because of this that's the plugin is not working.

Any help from you guys... Im using Openfire 3.10.3

Thanks!