Bug 1601819: Add crashtest for this no-longer-reproducible bug. (no review, crashtest-only)

Differential Revision: https://phabricator.services.mozilla.com/D166855

layout/generic/crashtests/1601819-1.html

@@ -0,0 +1,11 @@
+<style>
+* {
+  page-break-before: left;
+  display: grid;
+}
+</style>
+<details style="column-width: 0em" open>
+<form>
+<fieldset>
+<x>
+<datalist>

layout/generic/crashtests/crashtests.list

@@ -759,6 +759,7 @@ load 1586470.html
 load 1588955-very-large-frameset.html
 load 1590569.html
 load 1596310.html
+load 1601819-1.html
 skip load 1608851-1.html # bug 1639947
 load 1608851-2.html
 load 1613210.html