The ConcordanceParameterFrame.java file has the code line:
setTitle("" + useWebBrowser);
in the constructMiddlePanel() function.
This makes the title of the frame change between true and false every time the checkbox for 'Use a web browser to view the concordance' is checked or unchecked.
I guess this, must have been introduced for debugging and was never intended to be in the final product. It needs to be removed.