Lemma 3.1 of the paper, with reciprocal integer parameters. Let $K=2^{20}$. For every sufficiently large $E$, every $D>0$, and every lower bound $Q$, there is an exponent $q\geq\max\{3,Q\}$ with the following property. If $G$ is $q$-critical, $|V(G)|\leq D|X|$, and $E\deg_{G[X]}(x)<|X|$ for every $x\in X$, then $G$ contains a stable hubbed comb such that $E\leq Kt$ and $E|X|\leq Kt^2|B_i|$ for every block $B_i$.

The absolute constant $K$ replaces the constant $400$ in the paper to accommodate the integral form of Theorem 2.1. Its value does not affect the Erdős–Hajnal conclusion.