XXX and YYY should be on separate lines and not overlap, i.e. the height of .flex should not be 0.

XXX
YYY

Summary

Harness status: OK

Found 1 tests

Details

ResultTest NameMessage
Pass#container 1
Asserts run
Pass
assert_true(true, "data-expected-height is a valid data attribute")
    at checkDataKeys ( /resources/check-layout-th.js:61:13)