diff --git a/browser/themes/linux/jar.mn b/browser/themes/linux/jar.mn
index 253ddbacf62b..f967479dfc7a 100644
--- a/browser/themes/linux/jar.mn
+++ b/browser/themes/linux/jar.mn
@@ -278,7 +278,7 @@ browser.jar:
   skin/classic/browser/devtools/vview-edit.png              (../shared/devtools/images/vview-edit.png)
   skin/classic/browser/devtools/vview-open-inspector.png    (../shared/devtools/images/vview-open-inspector.png)
   skin/classic/browser/devtools/undock@2x.png               (../shared/devtools/images/undock@2x.png)
-  skin/classic/browser/devtools/font-inspector.css          (devtools/font-inspector.css)
+  skin/classic/browser/devtools/font-inspector.css          (../shared/devtools/font-inspector.css)
   skin/classic/browser/devtools/computedview.css            (devtools/computedview.css)
   skin/classic/browser/devtools/arrow-e.png                 (devtools/arrow-e.png)
   skin/classic/browser/devtools/responsiveui-rotate.png     (../shared/devtools/responsiveui-rotate.png)
diff --git a/browser/themes/osx/devtools/font-inspector.css b/browser/themes/osx/devtools/font-inspector.css
deleted file mode 100644
index fd3deefc1856..000000000000
--- a/browser/themes/osx/devtools/font-inspector.css
+++ /dev/null
@@ -1,78 +0,0 @@
-* {
-  box-sizing: border-box;
-}
-
-body {
-  margin: 0;
-  padding-bottom: 20px;
-}
-
-#all-fonts {
-  padding: 0;
-  margin: 0;
-}
-
-#showall {
-  border-radius: 0;
-  border: 1px solid black;
-  margin: 3px;
-  cursor: pointer;
-  position: fixed;
-  bottom: 0;
-  right: 0;
-}
-
-.font {
-  padding: 10px 10px;
-}
-
-.theme-dark .font {
-  border-bottom: 1px solid #444;
-}
-
-.theme-light .font {
-  border-bottom: 1px solid #DDD;
-}
-
-.font:last-of-type {
-  border-bottom: 0;
-}
-
-.theme-light .font:nth-child(even) {
-  background: #F4F4F4;
-}
-
-.font-preview {
-  height: 60px;
-  width: 100%;
-  border: 0;
-  display: block;
-}
-
-.font-info {
-  display: block;
-}
-
-.font-name {
-  display: inline;
-}
-
-.font-css-code {
-  max-width: 100%;
-  overflow: hidden;
-  text-overflow: ellipsis;
-  padding: 5px;
-}
-
-.theme-light .font-css-code,
-.theme-light .font-url {
-  border: 1px solid #CCC;
-  background: white;
-}
-
-.theme-dark .font-css-code,
-.theme-dark .font-url {
-  border: 1px solid #333;
-  background: black;
-  color: white;
-}
diff --git a/browser/themes/osx/jar.mn b/browser/themes/osx/jar.mn
index 3f973a8caf14..4bf68e901707 100644
--- a/browser/themes/osx/jar.mn
+++ b/browser/themes/osx/jar.mn
@@ -399,7 +399,7 @@ browser.jar:
   skin/classic/browser/devtools/vview-edit.png              (../shared/devtools/images/vview-edit.png)
   skin/classic/browser/devtools/vview-open-inspector.png    (../shared/devtools/images/vview-open-inspector.png)
   skin/classic/browser/devtools/undock@2x.png               (../shared/devtools/images/undock@2x.png)
-  skin/classic/browser/devtools/font-inspector.css          (devtools/font-inspector.css)
+  skin/classic/browser/devtools/font-inspector.css          (../shared/devtools/font-inspector.css)
   skin/classic/browser/devtools/computedview.css            (devtools/computedview.css)
   skin/classic/browser/devtools/arrow-e.png                 (devtools/arrow-e.png)
   skin/classic/browser/devtools/responsiveui-rotate.png     (../shared/devtools/responsiveui-rotate.png)
diff --git a/browser/themes/linux/devtools/font-inspector.css b/browser/themes/shared/devtools/font-inspector.css
similarity index 100%
rename from browser/themes/linux/devtools/font-inspector.css
rename to browser/themes/shared/devtools/font-inspector.css
diff --git a/browser/themes/windows/devtools/font-inspector.css b/browser/themes/windows/devtools/font-inspector.css
deleted file mode 100644
index fd3deefc1856..000000000000
--- a/browser/themes/windows/devtools/font-inspector.css
+++ /dev/null
@@ -1,78 +0,0 @@
-* {
-  box-sizing: border-box;
-}
-
-body {
-  margin: 0;
-  padding-bottom: 20px;
-}
-
-#all-fonts {
-  padding: 0;
-  margin: 0;
-}
-
-#showall {
-  border-radius: 0;
-  border: 1px solid black;
-  margin: 3px;
-  cursor: pointer;
-  position: fixed;
-  bottom: 0;
-  right: 0;
-}
-
-.font {
-  padding: 10px 10px;
-}
-
-.theme-dark .font {
-  border-bottom: 1px solid #444;
-}
-
-.theme-light .font {
-  border-bottom: 1px solid #DDD;
-}
-
-.font:last-of-type {
-  border-bottom: 0;
-}
-
-.theme-light .font:nth-child(even) {
-  background: #F4F4F4;
-}
-
-.font-preview {
-  height: 60px;
-  width: 100%;
-  border: 0;
-  display: block;
-}
-
-.font-info {
-  display: block;
-}
-
-.font-name {
-  display: inline;
-}
-
-.font-css-code {
-  max-width: 100%;
-  overflow: hidden;
-  text-overflow: ellipsis;
-  padding: 5px;
-}
-
-.theme-light .font-css-code,
-.theme-light .font-url {
-  border: 1px solid #CCC;
-  background: white;
-}
-
-.theme-dark .font-css-code,
-.theme-dark .font-url {
-  border: 1px solid #333;
-  background: black;
-  color: white;
-}
diff --git a/browser/themes/windows/jar.mn b/browser/themes/windows/jar.mn
index ab2f6d00d43d..9f55559737a1 100644
--- a/browser/themes/windows/jar.mn
+++ b/browser/themes/windows/jar.mn
@@ -314,7 +314,7 @@ browser.jar:
         skin/classic/browser/devtools/vview-edit.png                (../shared/devtools/images/vview-edit.png)
         skin/classic/browser/devtools/vview-open-inspector.png      (../shared/devtools/images/vview-open-inspector.png)
         skin/classic/browser/devtools/undock@2x.png                 (../shared/devtools/images/undock@2x.png)
-        skin/classic/browser/devtools/font-inspector.css            (devtools/font-inspector.css)
+        skin/classic/browser/devtools/font-inspector.css            (../shared/devtools/font-inspector.css)
         skin/classic/browser/devtools/computedview.css              (devtools/computedview.css)
         skin/classic/browser/devtools/arrow-e.png                   (devtools/arrow-e.png)
         skin/classic/browser/devtools/responsiveui-rotate.png       (../shared/devtools/responsiveui-rotate.png)
@@ -676,7 +676,7 @@ browser.jar:
         skin/classic/aero/browser/devtools/vview-edit.png            (../shared/devtools/images/vview-edit.png)
         skin/classic/aero/browser/devtools/vview-open-inspector.png  (../shared/devtools/images/vview-open-inspector.png)
         skin/classic/aero/browser/devtools/undock@2x.png             (../shared/devtools/images/undock@2x.png)
-        skin/classic/aero/browser/devtools/font-inspector.css        (devtools/font-inspector.css)
+        skin/classic/aero/browser/devtools/font-inspector.css        (../shared/devtools/font-inspector.css)
         skin/classic/aero/browser/devtools/computedview.css          (devtools/computedview.css)
         skin/classic/aero/browser/devtools/arrow-e.png               (devtools/arrow-e.png)
         skin/classic/aero/browser/devtools/responsiveui-rotate.png   (../shared/devtools/responsiveui-rotate.png)