diff --git a/test/lhs-test.html b/test/lhs-test.html
index 85e5d785d..d507aa19d 100644
--- a/test/lhs-test.html
+++ b/test/lhs-test.html
@@ -148,7 +148,6 @@
     }
     code{white-space: pre-wrap;}
     span.smallcaps{font-variant: small-caps;}
-    span.underline{text-decoration: underline;}
     div.column{display: inline-block; vertical-align: top; width: 50%;}
     div.hanging-indent{margin-left: 1.5em; text-indent: -1.5em;}
     ul.task-list{list-style: none;}
diff --git a/test/lhs-test.html+lhs b/test/lhs-test.html+lhs
index 32e0baf4d..a7f3e3a64 100644
--- a/test/lhs-test.html+lhs
+++ b/test/lhs-test.html+lhs
@@ -148,7 +148,6 @@
     }
     code{white-space: pre-wrap;}
     span.smallcaps{font-variant: small-caps;}
-    span.underline{text-decoration: underline;}
     div.column{display: inline-block; vertical-align: top; width: 50%;}
     div.hanging-indent{margin-left: 1.5em; text-indent: -1.5em;}
     ul.task-list{list-style: none;}
diff --git a/test/s5-basic.html b/test/s5-basic.html
index 3a225da83..5cf900d5c 100644
--- a/test/s5-basic.html
+++ b/test/s5-basic.html
@@ -13,7 +13,6 @@
   <style type="text/css">
     code{white-space: pre-wrap;}
     span.smallcaps{font-variant: small-caps;}
-    span.underline{text-decoration: underline;}
     div.column{display: inline-block; vertical-align: top; width: 50%;}
     div.hanging-indent{margin-left: 1.5em; text-indent: -1.5em;}
     ul.task-list{list-style: none;}
diff --git a/test/s5-fancy.html b/test/s5-fancy.html
index 00b25e80c..6da71525b 100644
--- a/test/s5-fancy.html
+++ b/test/s5-fancy.html
@@ -13,7 +13,6 @@
   <style type="text/css">
     code{white-space: pre-wrap;}
     span.smallcaps{font-variant: small-caps;}
-    span.underline{text-decoration: underline;}
     div.column{display: inline-block; vertical-align: top; width: 50%;}
     div.hanging-indent{margin-left: 1.5em; text-indent: -1.5em;}
     ul.task-list{list-style: none;}
diff --git a/test/s5-inserts.html b/test/s5-inserts.html
index 04dfc134a..5e84aa44f 100644
--- a/test/s5-inserts.html
+++ b/test/s5-inserts.html
@@ -11,7 +11,6 @@
   <style type="text/css">
     code{white-space: pre-wrap;}
     span.smallcaps{font-variant: small-caps;}
-    span.underline{text-decoration: underline;}
     div.column{display: inline-block; vertical-align: top; width: 50%;}
     div.hanging-indent{margin-left: 1.5em; text-indent: -1.5em;}
     ul.task-list{list-style: none;}
diff --git a/test/writer.html4 b/test/writer.html4
index 3e3fa9491..453277e9b 100644
--- a/test/writer.html4
+++ b/test/writer.html4
@@ -151,7 +151,6 @@
     }
     code{white-space: pre-wrap;}
     span.smallcaps{font-variant: small-caps;}
-    span.underline{text-decoration: underline;}
     div.column{display: inline-block; vertical-align: top; width: 50%;}
     div.hanging-indent{margin-left: 1.5em; text-indent: -1.5em;}
     ul.task-list{list-style: none;}
diff --git a/test/writer.html5 b/test/writer.html5
index 9c8670795..b4e5e953f 100644
--- a/test/writer.html5
+++ b/test/writer.html5
@@ -151,7 +151,6 @@
     }
     code{white-space: pre-wrap;}
     span.smallcaps{font-variant: small-caps;}
-    span.underline{text-decoration: underline;}
     div.column{display: inline-block; vertical-align: top; width: 50%;}
     div.hanging-indent{margin-left: 1.5em; text-indent: -1.5em;}
     ul.task-list{list-style: none;}