Description of problem:
as summary

Version-Release number of selected component (if applicable):
v3.8.10-1 on devel server

How reproducible:
100%

Steps to Reproduce:
1.open a test plan,https://tcms-devel.app.eng.nay.redhat.com/plan/10139/test-active#testcases
2.then choose the "Add cases from other plans" under the Cases tab
3.select Normal search and choose product as "Red Hat Enterprise Linux 5"and search out the cases.
4.then select all the cases and check what happened.

Actual results:
step 4: the browser has no response at all if you choose to select all the cases.

Expected results:
the browser can be slowly loading instead of dead there

Additional info:
It's better to add cases number that searched out in the beginning and ending .