diff --git a/css/userContent-files/webextension-tweaks/generic_style.css b/css/userContent-files/webextension-tweaks/generic_style.css
index ed598fe..ecc5635 100644
--- a/css/userContent-files/webextension-tweaks/generic_style.css
+++ b/css/userContent-files/webextension-tweaks/generic_style.css
@@ -281,3 +281,11 @@ url-prefix("moz-extension://{e4a8a97b-f2ed-450b-b12d-ee082ba24781}/src/content/e
     color: var(--theme-highlight-green)!important
   }
 }
+/*! Icons */
+/*! Redirector button for dark Firefox themes */
+toolbarbutton#toggle-button--redirectoreinaregilssoncom-redirector[image*=active] {
+  filter: invert(100%) brightness(600%)
+}
+toolbarbutton#toggle-button--redirectoreinaregilssoncom-redirector[image*=disabled] {
+  filter: invert(100%) brightness(250%)
+}
diff --git a/userContent.css b/userContent.css
index 03bf565..7d6a26d 100644
--- a/userContent.css
+++ b/userContent.css
@@ -1934,6 +1934,14 @@ url-prefix("moz-extension://{e4a8a97b-f2ed-450b-b12d-ee082ba24781}/src/content/e
     color: var(--theme-highlight-green)!important
   }
 }
+/*! Icons */
+/*! Redirector button for dark Firefox themes */
+toolbarbutton#toggle-button--redirectoreinaregilssoncom-redirector[image*=active] {
+  filter: invert(100%) brightness(600%)
+}
+toolbarbutton#toggle-button--redirectoreinaregilssoncom-redirector[image*=disabled] {
+  filter: invert(100%) brightness(250%)
+}
 @-moz-document url-prefix("moz-extension://{e4a8a97b-f2ed-450b-b12d-ee082ba24781}/") {
   body,
   html {