Unexpected “Missing or unrecognized delimiter for \bigg” for \uparrow #2689
Description
The following throws a unrecognized delimiter error in v3 but doesn't in v2 or "real" LaTeX.
\begin{equation*} \begin{array}{ccc}\operatorname {D}(Y) &\xrightarrow {\ \Phi \ } &\operatorname {D}^G(\mathbb{C}^n) \\\bigg {\uparrow }&& \bigg {\uparrow }\\\operatorname {D}_0(Y) &\xrightarrow {\ \Phi \ } &\operatorname {D}^G_0(\mathbb{C}^n) \end{array} \end{equation*}