Thanks. That worked. Project Browser was not displaying after I had put it on a side screen (running double displays).
The instruction you gave brought it back so it could be selected again and appeared again.
Also, I noticed other problems when I stretched the Chief Architect Window across both displays. Repositioning the Project Browser or others seemed problematic when the Chief Architect Window was spanning both screens, therefore I developed a practice to return the Chief Architect Window back to only a single display screen, when rearranging the tool bars, or the Project Browser, Library Browser.
I appreciate your help.
Jim