diff --git a/src/other/firefox/common/icons/universal-notepad-dark.svg b/src/other/firefox/common/icons/universal-notepad-dark.svg
new file mode 100644
index 00000000..2931a6e8
--- /dev/null
+++ b/src/other/firefox/common/icons/universal-notepad-dark.svg
@@ -0,0 +1,3 @@
+<svg version="1.1" viewBox="0 0 16 16" xmlns="http://www.w3.org/2000/svg">
+ <path d="m5.4746 0c-0.26491 0.013342-0.47461 0.23166-0.47461 0.5v0.5h-2c-1.108 0-2 0.892-2 2v11c0 1.108 0.892 2 2 2h10c1.108 0 2-0.892 2-2v-11c0-1.108-0.892-2-2-2h-2v-0.5c0-0.277-0.223-0.5-0.5-0.5s-0.5 0.223-0.5 0.5v0.5h-4v-0.5c0-0.277-0.223-0.5-0.5-0.5-0.0086562 0-0.016845-4.3039e-4 -0.02539 0zm-2.4746 2h9.9999c0.554 0 1 0.446 1 1v11c0 0.554-0.446 1-1 1h-10c-0.554 0-1-0.446-1-1v-11c0-0.554 0.446-1 1-1zm1.4982 3c-0.277 0-0.5 0.223-0.5 0.5s0.223 0.5 0.5 0.5h7.0017c0.277 0 0.5-0.223 0.5-0.5s-0.223-0.5-0.5-0.5zm0 3c-0.277 0-0.5 0.223-0.5 0.5s0.223 0.5 0.5 0.5h7.0017c0.277 0 0.5-0.223 0.5-0.5s-0.223-0.5-0.5-0.5zm0 3c-0.277 0-0.5 0.223-0.5 0.5s0.223 0.5 0.5 0.5h7.0017c0.277 0 0.5-0.223 0.5-0.5s-0.223-0.5-0.5-0.5z" fill="#ffffff"/>
+</svg>
diff --git a/src/other/firefox/common/parts/icons.css b/src/other/firefox/common/parts/icons.css
index 6aff10cc..1940500a 100644
--- a/src/other/firefox/common/parts/icons.css
+++ b/src/other/firefox/common/parts/icons.css
@@ -738,6 +738,14 @@ toolbar:not([brighttext]) .webextension-browser-action:-moz-lwtheme {
 	list-style-image: url("../icons/universal-notepad.svg") !important;
 }
 
+@media (prefers-color-scheme: dark) {
+#notes_mozilla_com-BAP .toolbarbutton-icon,
+#sidebarswitcher_menu_notes_mozilla_com-sidebar-action,
+#sidebar-box[sidebarcommand="notes_mozilla_com-sidebar-action"] > #sidebar-header > #sidebar-switcher-target > #sidebar-icon {
+	list-style-image: url("../icons/universal-notepad-dark.svg") !important;
+}
+}
+
 /* Fix flat buttons icons aproach */
 button.close::before {
 	content: "";