When click the "Go Back" button, the style of the page is mess

For Example:
1. The first, login the HR:
http://demo-old-ofbiz.apache.org/humanres/control/main?externalLoginKey=EL185424107487
2. In the HR Main page, click the company link:
Then clink the "update" button in the "Contact Information" screen,
3. After click the update button, the url of page is
"http://demo-old-ofbiz.apache.org/humanres/control/editcontactmech?partyId=Company犉 쭌秈=9000"
4. The rending page is very mess, looks like css missing.

Somebody can help me, thank you very much.
The attachment is my screen copy.