diff --git a/required/latex-lab/changes.txt b/required/latex-lab/changes.txt
index aebc41c91..3118ce810 100644
--- a/required/latex-lab/changes.txt
+++ b/required/latex-lab/changes.txt
@@ -1,3 +1,6 @@
+2024-01-29 Ulrike Fischer <Ulrike.Fischer@latex-project.org> 
+	* latex-lab-math.dtx: disable mathgrabbing in begindocument hook.
+
 2024-01-18 Ulrike Fischer <Ulrike.Fischer@latex-project.org> 
 	* latex-lab-firstaid.dtx: add support for \authors from amsart.
 
diff --git a/required/latex-lab/latex-lab-math.dtx b/required/latex-lab/latex-lab-math.dtx
index 802ba5434..5fd0dec0c 100644
--- a/required/latex-lab/latex-lab-math.dtx
+++ b/required/latex-lab/latex-lab-math.dtx
@@ -1828,6 +1828,20 @@
   }
 %    \end{macrocode}
 % \end{macro}
+% 
+% \subsection{Disable math grabbing in the begindocument hook}
+% For example amsart uses math to measure text there.
+% 
+%    \begin{macrocode}
+\tl_gput_right:Nn\@kernel@before@begindocument
+  {
+    \bool_set_true:N\l__math_collected_bool
+  }
+\tl_gput_right:Nn\@kernel@after@begindocument
+ {
+   \bool_set_false:N\l__math_collected_bool
+ }
+%    \end{macrocode}
 %
 % \subsection{Modifying \pkg{amsmath}}
 %