diff --git a/components/style/gecko/media_features.rs b/components/style/gecko/media_features.rs
index 93dc085cd69..9f36a3ec846 100644
--- a/components/style/gecko/media_features.rs
+++ b/components/style/gecko/media_features.rs
@@ -406,45 +406,6 @@ fn eval_prefers_color_scheme(device: &Device, query_value: Option<PrefersColorSc
     }
 }
 
-/// Values for the -moz-toolbar-prefers-color-scheme media feature.
-#[derive(Clone, Copy, Debug, FromPrimitive, Parse, PartialEq, ToCss)]
-#[repr(u8)]
-enum ToolbarPrefersColorScheme {
-    Dark,
-    Light,
-    System,
-}
-
-/// The color-scheme of the toolbar in the current Firefox theme. This is based
-/// on a pref managed by the front-end.
-fn eval_toolbar_prefers_color_scheme(d: &Device, query_value: Option<ToolbarPrefersColorScheme>) -> bool {
-    let toolbar_value = match static_prefs::pref!("browser.theme.toolbar-theme") {
-        0 => ToolbarPrefersColorScheme::Dark,
-        1 => ToolbarPrefersColorScheme::Light,
-        _ => ToolbarPrefersColorScheme::System,
-    };
-
-    let query_value = match query_value {
-        Some(v) => v,
-        None => return true,
-    };
-
-    if query_value == toolbar_value {
-        return true;
-    }
-
-    if toolbar_value != ToolbarPrefersColorScheme::System {
-        return false;
-    }
-
-    // System might match light and dark as well.
-    match query_value {
-        ToolbarPrefersColorScheme::Dark => eval_prefers_color_scheme(d, Some(PrefersColorScheme::Dark)),
-        ToolbarPrefersColorScheme::Light => eval_prefers_color_scheme(d, Some(PrefersColorScheme::Light)),
-        ToolbarPrefersColorScheme::System => true,
-    }
-}
-
 bitflags! {
     /// https://drafts.csswg.org/mediaqueries-4/#mf-interaction
     struct PointerCapabilities: u8 {
@@ -690,7 +651,7 @@ macro_rules! bool_pref_feature {
 /// to support new types in these entries and (2) ensuring that either
 /// nsPresContext::MediaFeatureValuesChanged is called when the value that
 /// would be returned by the evaluator function could change.
-pub static MEDIA_FEATURES: [MediaFeatureDescription; 61] = [
+pub static MEDIA_FEATURES: [MediaFeatureDescription; 60] = [
     feature!(
         atom!("width"),
         AllowsRanges::Yes,
@@ -900,12 +861,6 @@ pub static MEDIA_FEATURES: [MediaFeatureDescription; 61] = [
         Evaluator::BoolInteger(eval_moz_non_native_content_theme),
         ParsingRequirements::CHROME_AND_UA_ONLY,
     ),
-    feature!(
-        atom!("-moz-toolbar-prefers-color-scheme"),
-        AllowsRanges::No,
-        keyword_evaluator!(eval_toolbar_prefers_color_scheme, ToolbarPrefersColorScheme),
-        ParsingRequirements::CHROME_AND_UA_ONLY,
-    ),
     feature!(
         atom!("-moz-windows-non-native-menus"),
         AllowsRanges::No,