If $\mathbb{G}$ is a 2-group, does there always exists a short exact sequence for this $\mathbb{G}$, such that

$$ 0 \to BG_b \to \mathbb{G} \to G_a \to 0? $$ where both $G_a$ and $G_b$ are nontrivial (say, non-identity groups)?

(This is the following question of $\mathbf{B}A$ as a 2-group in a long fiber sequence approach from an opposite viewpoint.)


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