Let $X$ be a stable curve of genus $g$ over the field $k$, i.e., a $k$-rational point of the Deligne-Mumford stack $M_g$.
What is the genus of the normalization of $X$? Does it depend on the number of singularities of $X$?
Note that the normalization of $X$ is a smooth curve. It is still geometrically connected and it is projective.