Steps to reproduce:

1.Open the editor for a page
2.Open the latex window and insert "\sqrt\pi"
3.Click on the "<" button to close the latex window
4.Copy the formula immediately
5.Paste it onto another page

Observed Result:
The math elements does not appear on the page after pasting.However after saving it appears there are multiple of those

Test Environment: https://test2.wikipedia.org/
Browser: Chrome Version 26.0.1410.65
OS: MAC OS X 10. 8. 5
Page:https://test2.wikipedia.org/wiki/19th_december?veaction=edit

Version: unspecified
Severity: normal