diff --git a/components/style/properties/longhand/ui.mako.rs b/components/style/properties/longhand/ui.mako.rs
index cd537677f6f..045627e004c 100644
--- a/components/style/properties/longhand/ui.mako.rs
+++ b/components/style/properties/longhand/ui.mako.rs
@@ -9,12 +9,16 @@
 // https://drafts.csswg.org/css-ui-3/
 <% data.new_style_struct("UI", inherited=False, gecko_name="UIReset") %>
 
+// TODO spec says that UAs should not support this
+// we should probably remove from gecko (https://bugzilla.mozilla.org/show_bug.cgi?id=1328331)
 ${helpers.single_keyword("ime-mode", "normal auto active disabled inactive",
                          products="gecko", gecko_ffi_name="mIMEMode",
-                         animatable=False)}
+                         animatable=False,
+                         spec="https://drafts.csswg.org/css-ui/#input-method-editor")}
 
 ${helpers.single_keyword("-moz-user-select", "auto text none all", products="gecko",
                          gecko_ffi_name="mUserSelect",
                          gecko_enum_prefix="StyleUserSelect",
                          gecko_inexhaustive=True,
-                         animatable=False)}
+                         animatable=False,
+                         spec="https://drafts.csswg.org/css-ui-4/#propdef-user-select")}