No Images effect

Hello,
I installed the Diary theme an wrote an article with an image inside.
When I klick on the Image, it opens like a new site not with this Image effect.

What do I wrong?
Maybe any settings?

Need some help.
Thank you.

• This topic was modified 7 hours, 46 minutes ago by  zeeroo.
• This topic was modified 7 hours, 45 minutes ago by  zeeroo.