This chapter deals with an additional technical difficulty of Morse–Bott homology when adapted to the semi-infinite dimensional setup encountered in Floer theory. The main obstruction for achieving compactness of the relevant moduli spaces is the occurrence of pseudo-holomorphic bubbles. Via a suitable geometrical assumption one can avoid them, but considering convergence modulo bubbling is important in generalising Hamiltonian Floer theory to different setups. This is where the advantage of formulating Floer theory via polyfolds comes into play.