diff --git a/components/style/values/specified/table.rs b/components/style/values/specified/table.rs
index cd2bfa96c5d..79136b12ca1 100644
--- a/components/style/values/specified/table.rs
+++ b/components/style/values/specified/table.rs
@@ -4,6 +4,8 @@
 
 //! Specified types for CSS values related to tables.
 
+use crate::parser::ParserContext;
+
 /// Specified values for the `caption-side` property.
 ///
 /// Note that despite having "physical" names, these are actually interpreted
@@ -12,6 +14,11 @@
 /// line-start and -end.
 ///
 /// https://drafts.csswg.org/css-tables/#propdef-caption-side
+#[cfg(feature = "gecko")]
+fn caption_side_non_standard_enabled(_context: &ParserContext) -> bool {
+    static_prefs::pref!("layout.css.caption-side-non-standard.enabled")
+}
+
 #[allow(missing_docs)]
 #[derive(
     Clone,
@@ -35,11 +42,15 @@ pub enum CaptionSide {
     Top,
     Bottom,
     #[cfg(feature = "gecko")]
+    #[parse(condition = "caption_side_non_standard_enabled")]
     Right,
     #[cfg(feature = "gecko")]
+    #[parse(condition = "caption_side_non_standard_enabled")]
     Left,
     #[cfg(feature = "gecko")]
+    #[parse(condition = "caption_side_non_standard_enabled")]
     TopOutside,
     #[cfg(feature = "gecko")]
+    #[parse(condition = "caption_side_non_standard_enabled")]
     BottomOutside,
 }