diff --git a/browser/themes/gnomestripe/browser/preferences/preferences.css b/browser/themes/gnomestripe/browser/preferences/preferences.css
index 0d12362f6fb..f0790cf687c 100644
--- a/browser/themes/gnomestripe/browser/preferences/preferences.css
+++ b/browser/themes/gnomestripe/browser/preferences/preferences.css
@@ -103,11 +103,11 @@ filefield {
   margin: 1px;
 }
 
-filefield[disabled="true"] .fileFieldContentBox {
+.fileFieldContentBox[disabled="true"] {
   opacity: 0.5;
 }
 
-filefield[disabled="true"] .fileFieldIcon {
+.fileFieldIcon[disabled="true"] {
   opacity: 0.2;
 }
 
diff --git a/browser/themes/winstripe/browser/preferences/preferences.css b/browser/themes/winstripe/browser/preferences/preferences.css
index 10c940dae6b..1030c0ce335 100644
--- a/browser/themes/winstripe/browser/preferences/preferences.css
+++ b/browser/themes/winstripe/browser/preferences/preferences.css
@@ -130,11 +130,11 @@ filefield {
   margin: 1px;
 }
 
-filefield[disabled="true"] .fileFieldContentBox {
+.fileFieldContentBox[disabled="true"] {
   opacity: 0.5;
 }
 
-filefield[disabled="true"] .fileFieldIcon {
+.fileFieldIcon[disabled="true"] {
   opacity: 0.2;
 }
 
diff --git a/toolkit/mozapps/preferences/preferences.xml b/toolkit/mozapps/preferences/preferences.xml
index d410e3e418a..8b9b5c21f78 100644
--- a/toolkit/mozapps/preferences/preferences.xml
+++ b/toolkit/mozapps/preferences/preferences.xml
@@ -8,8 +8,8 @@
   <binding id="fileField" extends="chrome://global/content/bindings/general.xml#control-item">
     <content>
       <xul:stringbundle anonid="bundle" src="chrome://mozapps/locale/preferences/preferences.properties"/>
-      <xul:hbox class="fileFieldContentBox" align="center" flex="1">
-        <xul:image class="fileFieldIcon" xbl:inherits="src=image"/>
+      <xul:hbox class="fileFieldContentBox" align="center" flex="1" xbl:inherits="disabled">
+        <xul:image class="fileFieldIcon" xbl:inherits="src=image,disabled"/>
         <xul:textbox class="fileFieldLabel" xbl:inherits="value=label,disabled,accesskey,tabindex" flex="1" readonly="true"/>
       </xul:hbox>
     </content>