In the demo app, go to https://demo-stable.ofbiz.apache.org/humanres/control/FindEmplPositions, click on New Employee Position, and toggle one of the four flags, e.g. set Temporary Flag to N.
Now on the Find screen, there is no way to find all employee positions: it insists on a Yes or No for the flags. This patch allows a blank "don't care" option.
Thanks to Larissa Zanoni at Blockfreight for discovering this issue.