diff --git a/toolkit/themes/shared/in-content/info-pages.inc.css b/toolkit/themes/shared/in-content/info-pages.inc.css
index 4889602a09..29fcbe1ea8 100644
--- a/toolkit/themes/shared/in-content/info-pages.inc.css
+++ b/toolkit/themes/shared/in-content/info-pages.inc.css
@@ -96,7 +96,7 @@ ul {
 /* Trees */
 .tree-container {
   margin-top: 1.2em;
-  flex-grow: 1;
+  flex: 1 0px;
   min-height: 12em;
 }