diff --git a/css/leptonContent.css b/css/leptonContent.css
index 327a24c..f47ec7e 100644
--- a/css/leptonContent.css
+++ b/css/leptonContent.css
@@ -2790,7 +2790,7 @@
 @supports -moz-bool-pref("userChrome.rounding.square_button") {
   @-moz-document url-prefix("about:"), regexp("^chrome://\\w+/content/.*.xhtml$")
   {
-    button,
+    button:not(.toggle-button),
     .close-icon,
     .action-icon::before,
     .web-appearance-choice,
diff --git a/src/contents/_rounding.scss b/src/contents/_rounding.scss
index b0452d1..c7a3f48 100644
--- a/src/contents/_rounding.scss
+++ b/src/contents/_rounding.scss
@@ -3,7 +3,7 @@
     url-prefix "about:",
     regexp "^chrome:\/\/\\w+\/content\/.*\.xhtml$"
   ) {
-    button,
+    button:not(.toggle-button),
     .close-icon,
     .action-icon::before,
     .web-appearance-choice,