diff --git a/Userland/Libraries/LibWeb/CSS/Identifiers.json b/Userland/Libraries/LibWeb/CSS/Identifiers.json
index 15238673b1..81c09ca0d0 100644
--- a/Userland/Libraries/LibWeb/CSS/Identifiers.json
+++ b/Userland/Libraries/LibWeb/CSS/Identifiers.json
@@ -57,6 +57,7 @@
   "-libweb-palette-window-text",
   "absolute",
   "alias",
+  "all",
   "all-scroll",
   "anywhere",
   "auto",
@@ -75,8 +76,10 @@
   "circle",
   "clip",
   "col-resize",
+  "collapse",
   "column",
   "column-reverse",
+  "contain",
   "content",
   "content-box",
   "context-menu",
@@ -98,6 +101,7 @@
   "flex",
   "flex-start",
   "flex-end",
+  "from-font",
   "full-size-kana",
   "full-width",
   "grab",
@@ -107,6 +111,7 @@
   "hidden",
   "inline",
   "inline-block",
+  "inline-table",
   "inset",
   "inside",
   "invert",
@@ -118,6 +123,7 @@
   "lighter",
   "line-through",
   "list-item",
+  "local",
   "lowercase",
   "lower-alpha",
   "lower-latin",
@@ -165,6 +171,7 @@
   "separate",
   "serif",
   "small",
+  "small-caps",
   "smaller",
   "solid",
   "space",
@@ -190,6 +197,8 @@
   "text",
   "text-bottom",
   "text-top",
+  "thick",
+  "thin",
   "top",
   "ui-monospace",
   "ui-rounded",