We explore (weak) continuity properties of group operations. For this purpose, the Novak number and developability number are applied. It is shown that if $(G,·,\tau )$ is a regular right (left) semitopological group with $\mathrm{dev}\left(G\right)<\mathrm{Nov}\left(G\right)$ such that all left (right) translations are feebly continuous, then $(G,·,\tau )$ is a topological group. This extends several results in literature.