diff --git a/layout/html/document/src/quirk.css b/layout/html/document/src/quirk.css
index 42d1b34a5f0..d068d2b89f7 100644
--- a/layout/html/document/src/quirk.css
+++ b/layout/html/document/src/quirk.css
@@ -290,7 +290,7 @@ img[align=right] {
  * Quirk: Use border-box box sizing for text inputs, password inputs, and
  * textareas.  (b=184478 on why we use content-box sizing in standards mode)
  */
-input, textarea {
+input:not([type=image]), textarea {
   /* Note that all other <input>s already use border-box
      sizing, so we're ok with this selector */
   -moz-box-sizing: border-box;
diff --git a/layout/style/quirk.css b/layout/style/quirk.css
index 42d1b34a5f0..d068d2b89f7 100644
--- a/layout/style/quirk.css
+++ b/layout/style/quirk.css
@@ -290,7 +290,7 @@ img[align=right] {
  * Quirk: Use border-box box sizing for text inputs, password inputs, and
  * textareas.  (b=184478 on why we use content-box sizing in standards mode)
  */
-input, textarea {
+input:not([type=image]), textarea {
   /* Note that all other <input>s already use border-box
      sizing, so we're ok with this selector */
   -moz-box-sizing: border-box;