What steps will reproduce the problem?
(1) Click "Choose Tryjobs"
(2) Type "layout" into filter, and check "linux_layout_tests_layout_ng"
(3) Type "um_rel_ng" into filter.

What is the expected result?

List of matching results, with none of them being checked: 
linux_chromium_rel_ng
mac_chromium_rel_ng
win7_chromium_rel_ng

What happens instead?

mac_chromium_rel_ng is checked. 

Probable cause:
linux_layout_tests_layout_ng which I checked is in the 2nd position.
mac_chromim_rel_ng which gets checked by accident is also in 2nd position.

This unexpectedly selected checkbox will not cause "mac_chromium_rel_ng" to run (thankfully). It is just annoying.