I've noticed a strange behavior when attempting to filter on a text field in workflow results browser. When I select the filter option, String Equals is the default selection in the dropdown list, but the area to enter my search text is initially greyed out and unavailable. However, if I change it to String Contains, I can enter the text and the filter works properly. This means I'm going to potentially see results that don't match my desired result exactly, as long as the text I enter is included somewhere in the items queried.
Is there a reason that the String Equals selection is unavailable for filtering a text field? It seems that if I wait a minute or two the String Equals option then becomes available. Does it take some time for the results to be read into memory so the String Equals function is available?