diff --git a/scss/_reboot.scss b/scss/_reboot.scss
index 4cb858f8803c..6c294ce5a088 100644
--- a/scss/_reboot.scss
+++ b/scss/_reboot.scss
@@ -28,7 +28,6 @@ html {
   font-family: sans-serif; // 2
   line-height: 1.15; // 3
   -webkit-text-size-adjust: 100%; // 4
-  -ms-text-size-adjust: 100%; // 4
   -ms-overflow-style: scrollbar; // 5
   -webkit-tap-highlight-color: rgba($black, 0); // 6
 }
@@ -41,6 +40,7 @@ html {
 }
 
 // Shim for "new" HTML5 structural elements to display correctly (IE10, older browsers)
+// TODO: remove in v5
 // stylelint-disable-next-line selector-list-comma-newline-after
 article, aside, figcaption, figure, footer, header, hgroup, main, nav, section {
   display: block;
@@ -157,10 +157,6 @@ blockquote {
   margin: 0 0 1rem;
 }
 
-dfn {
-  font-style: italic; // Add the correct font style in Android 4.3-
-}
-
 b,
 strong {
   font-weight: bolder; // Add the correct font weight in Chrome, Edge, and Safari
@@ -349,7 +345,7 @@ select {
 //    controls in Android 4.
 // 2. Correct the inability to style clickable types in iOS and Safari.
 button,
-html [type="button"], // 1
+[type="button"], // 1
 [type="reset"],
 [type="submit"] {
   -webkit-appearance: button; // 2
@@ -439,7 +435,6 @@ progress {
 // Remove the inner padding and cancel buttons in Chrome and Safari on macOS.
 //
 
-[type="search"]::-webkit-search-cancel-button,
 [type="search"]::-webkit-search-decoration {
   -webkit-appearance: none;
 }