It would have happened to me again. I mean the long trial and error and the wage wait process to find errors in XPages. For some reason, my XPage would not open up if I remove the XPageDebugToolbar_v3.0.1 custom control from my XPage. And again it worked if I added it back again.
I was like 0.o why would this happen. Has the Debug toolbar author found a way to mess up XPages if they dont need them anymore :P.
Fortunately I remember that one of my dynamic view controls used a managed bean in which I had declared an object reference to the debug tool bar
private static final DebugToolbar dBar = DebugToolbar.get();
to the answer was to put "//" before the line of code and make it
//private static final DebugToolbar dBar = DebugToolbar.get();
Yeah. Comment-ing the code fixed the issue. Wierd. Guess it would have been better it does not error out and surprice like this.