ofxBox2d shouldRemoveOffScreen causing massive framedrop in FULLSCREEN

Hey all
i am on of 0.98 Osx. if i run ofxBox2d in fullscreen mode, there is a massive framedrop apparently caused by
ofxBox2dBaseShape::shouldRemoveOffScreen. I believe its because of ofGetWidth() and ofGetHeight() calls in ofxBox2dBaseShape::shouldRemoveOffScreen;

I am not sure how to fix the shouldRemoveOffScreen function as its called through
ofRemove(boxes, ofxBox2dBaseShape::shouldRemoveOffScreen) in the updateloop.

first thought is to get ofGetWidth() after switching to fullscreen somewhere outside the update loop and then pass it just to shouldRemoveOffScreen(). But i am not c++ enough to get how pass a parameter to this kind of construction…

thanks for any syntax or design pattern advice