diff --git a/css/leptonChrome.css b/css/leptonChrome.css
index c4f72c61..d60f410f 100644
--- a/css/leptonChrome.css
+++ b/css/leptonChrome.css
@@ -208,7 +208,12 @@
     /*= Linux - Titlebar button at lwtheme =====================================*/
     @supports not -moz-bool-pref("userChrome.compatibility.os.linux_non_native_titlebar_button") {
       :root:is(:-moz-lwtheme, [lwtheme]) .titlebar-button {
+        appearance: none !important;
+      }
+      :root:is(:-moz-lwtheme, [lwtheme]) .titlebar-button > .toolbarbutton-icon {
         appearance: auto !important;
+        width: unset !important;
+        height: unset !important;
       }
       :root:is(:-moz-lwtheme, [lwtheme]) .titlebar-min,
       :root:is(:-moz-lwtheme, [lwtheme]) .titlebar-max,
@@ -13690,7 +13695,12 @@
 }
 @media (-moz-bool-pref: "userChrome.compatibility.os") and (-moz-gtk-csd-available) and (not (-moz-bool-pref: "userChrome.compatibility.os.linux_non_native_titlebar_button")) {
   :root:is(:-moz-lwtheme, [lwtheme]) .titlebar-button {
+    appearance: none !important;
+  }
+  :root:is(:-moz-lwtheme, [lwtheme]) .titlebar-button > .toolbarbutton-icon {
     appearance: auto !important;
+    width: unset !important;
+    height: unset !important;
   }
   :root:is(:-moz-lwtheme, [lwtheme]) .titlebar-min,
   :root:is(:-moz-lwtheme, [lwtheme]) .titlebar-max,
diff --git a/css/leptonChromeESR.css b/css/leptonChromeESR.css
index 3c1a4bb1..8cc1c8b9 100644
--- a/css/leptonChromeESR.css
+++ b/css/leptonChromeESR.css
@@ -337,7 +337,12 @@
     /*= Linux - Titlebar button at lwtheme =====================================*/
     @supports not -moz-bool-pref("userChrome.compatibility.os.linux_non_native_titlebar_button") {
       :root:is(:-moz-lwtheme, [lwtheme]) .titlebar-button {
+        appearance: none !important;
+      }
+      :root:is(:-moz-lwtheme, [lwtheme]) .titlebar-button > .toolbarbutton-icon {
         appearance: auto !important;
+        width: unset !important;
+        height: unset !important;
       }
       :root:is(:-moz-lwtheme, [lwtheme]) .titlebar-min,
       :root:is(:-moz-lwtheme, [lwtheme]) .titlebar-max,
diff --git a/src/compatibility/_os.scss b/src/compatibility/_os.scss
index f546907e..db4ace78 100644
--- a/src/compatibility/_os.scss
+++ b/src/compatibility/_os.scss
@@ -172,7 +172,12 @@
   @include NotOption("userChrome.compatibility.os.linux_non_native_titlebar_button") {
     @include lwtheme {
       .titlebar-button {
-        appearance: auto !important;
+        appearance: none !important;
+        > .toolbarbutton-icon {
+          appearance: auto !important;
+          width: unset !important;
+          height: unset !important;
+        }
       }
       .titlebar-min,
       .titlebar-max,