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diff --git a/servo/components/style/values/resolved/counters.rs b/servo/components/style/values/resolved/counters.rs
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+++ b/servo/components/style/values/resolved/counters.rs
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+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+//! Resolved values for counter properties
+
+use super::{Context, ToResolvedValue};
+use crate::values::computed;
+
+/// https://drafts.csswg.org/css-content/#content-property
+///
+/// We implement this at resolved value time because otherwise it causes us to
+/// allocate a bunch of useless initial structs for ::before / ::after, which is
+/// a bit unfortunate.
+///
+/// Though these should be temporary, mostly, so if this causes complexity in
+/// other places, it should be fine to move to `StyleAdjuster`.
+///
+/// See https://github.com/w3c/csswg-drafts/issues/4632 for where some related
+/// issues are being discussed.
+impl ToResolvedValue for computed::Content {
+    type ResolvedValue = Self;
+
+    #[inline]
+    fn to_resolved_value(self, context: &Context) -> Self {
+        let (is_pseudo, is_before_or_after, is_marker) = match context.style.pseudo() {
+            Some(ref pseudo) => (true, pseudo.is_before_or_after(), pseudo.is_marker()),
+            None => (false, false, false),
+        };
+        match self {
+            Self::Normal if is_before_or_after => Self::None,
+            // For now, make `content: none` compute to `normal` for pseudos
+            // other than ::before, ::after and ::marker, as we don't respect it.
+            // https://github.com/w3c/csswg-drafts/issues/6124
+            // Ditto for non-pseudo elements if the pref is disabled.
+            Self::None
+                if (is_pseudo && !is_before_or_after && !is_marker) ||
+                    (!is_pseudo &&
+                        !static_prefs::pref!("layout.css.element-content-none.enabled")) =>
+            {
+                Self::Normal
+            },
+            other => other,
+        }
+    }
+
+    #[inline]
+    fn from_resolved_value(resolved: Self) -> Self {
+        resolved
+    }
+}