diff --git a/Userland/Libraries/LibWeb/CSS/CSSSupportsRule.cpp b/Userland/Libraries/LibWeb/CSS/CSSSupportsRule.cpp
index d318e8d811..901cdb3396 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSSupportsRule.cpp
+++ b/Userland/Libraries/LibWeb/CSS/CSSSupportsRule.cpp
@@ -30,7 +30,7 @@ void CSSSupportsRule::initialize(JS::Realm& realm)
 
 DeprecatedString CSSSupportsRule::condition_text() const
 {
-    return m_supports->to_string().release_value_but_fixme_should_propagate_errors().to_deprecated_string();
+    return m_supports->to_string().to_deprecated_string();
 }
 
 void CSSSupportsRule::set_condition_text(DeprecatedString text)
diff --git a/Userland/Libraries/LibWeb/CSS/Supports.cpp b/Userland/Libraries/LibWeb/CSS/Supports.cpp
index 15e129b981..b88228ce23 100644
--- a/Userland/Libraries/LibWeb/CSS/Supports.cpp
+++ b/Userland/Libraries/LibWeb/CSS/Supports.cpp
@@ -74,43 +74,43 @@ bool Supports::Feature::evaluate() const
         });
 }
 
-ErrorOr<String> Supports::Declaration::to_string() const
+String Supports::Declaration::to_string() const
 {
-    return String::formatted("({})", declaration);
+    return MUST(String::formatted("({})", declaration));
 }
 
-ErrorOr<String> Supports::Selector::to_string() const
+String Supports::Selector::to_string() const
 {
-    return String::formatted("selector({})", selector);
+    return MUST(String::formatted("selector({})", selector));
 }
 
-ErrorOr<String> Supports::Feature::to_string() const
+String Supports::Feature::to_string() const
 {
     return value.visit([](auto& it) { return it.to_string(); });
 }
 
-ErrorOr<String> Supports::InParens::to_string() const
+String Supports::InParens::to_string() const
 {
     return value.visit(
-        [](NonnullOwnPtr<Condition> const& condition) -> ErrorOr<String> { return String::formatted("({})", TRY(condition->to_string())); },
-        [](Supports::Feature const& it) -> ErrorOr<String> { return it.to_string(); },
-        [](GeneralEnclosed const& it) -> ErrorOr<String> { return it.to_string(); });
+        [](NonnullOwnPtr<Condition> const& condition) { return MUST(String::formatted("({})", condition->to_string())); },
+        [](Supports::Feature const& it) { return it.to_string(); },
+        [](GeneralEnclosed const& it) { return it.to_string(); });
 }
 
-ErrorOr<String> Supports::Condition::to_string() const
+String Supports::Condition::to_string() const
 {
     switch (type) {
     case Type::Not:
-        return String::formatted("not {}", TRY(children.first().to_string()));
+        return MUST(String::formatted("not {}", children.first().to_string()));
     case Type::And:
-        return String::join(" and "sv, children);
+        return MUST(String::join(" and "sv, children));
     case Type::Or:
-        return String::join(" or "sv, children);
+        return MUST(String::join(" or "sv, children));
     }
     VERIFY_NOT_REACHED();
 }
 
-ErrorOr<String> Supports::to_string() const
+String Supports::to_string() const
 {
     return m_condition->to_string();
 }
diff --git a/Userland/Libraries/LibWeb/CSS/Supports.h b/Userland/Libraries/LibWeb/CSS/Supports.h
index 826b80a208..a531f88d47 100644
--- a/Userland/Libraries/LibWeb/CSS/Supports.h
+++ b/Userland/Libraries/LibWeb/CSS/Supports.h
@@ -25,20 +25,20 @@ public:
         String declaration;
         JS::Handle<JS::Realm> realm;
         bool evaluate() const;
-        ErrorOr<String> to_string() const;
+        String to_string() const;
     };
 
     struct Selector {
         String selector;
         JS::Handle<JS::Realm> realm;
         bool evaluate() const;
-        ErrorOr<String> to_string() const;
+        String to_string() const;
     };
 
     struct Feature {
         Variant<Declaration, Selector> value;
         bool evaluate() const;
-        ErrorOr<String> to_string() const;
+        String to_string() const;
     };
 
     struct Condition;
@@ -46,7 +46,7 @@ public:
         Variant<NonnullOwnPtr<Condition>, Feature, GeneralEnclosed> value;
 
         bool evaluate() const;
-        ErrorOr<String> to_string() const;
+        String to_string() const;
     };
 
     struct Condition {
@@ -59,7 +59,7 @@ public:
         Vector<InParens> children;
 
         bool evaluate() const;
-        ErrorOr<String> to_string() const;
+        String to_string() const;
     };
 
     static NonnullRefPtr<Supports> create(NonnullOwnPtr<Condition>&& condition)
@@ -68,7 +68,7 @@ public:
     }
 
     bool matches() const { return m_matches; }
-    ErrorOr<String> to_string() const;
+    String to_string() const;
 
 private:
     Supports(NonnullOwnPtr<Condition>&&);
@@ -83,6 +83,6 @@ template<>
 struct AK::Formatter<Web::CSS::Supports::InParens> : AK::Formatter<StringView> {
     ErrorOr<void> format(FormatBuilder& builder, Web::CSS::Supports::InParens const& in_parens)
     {
-        return Formatter<StringView>::format(builder, TRY(in_parens.to_string()));
+        return Formatter<StringView>::format(builder, in_parens.to_string());
     }
 };