Update the migration guide

Mention some removed CSS extensions.

diff --git a/docs/reference/gtk/migrating-3to4.xml b/docs/reference/gtk/migrating-3to4.xml
index e8ce306112f8c1591999a0e5805cd837d8024c61..c9d946eb64a2236349518819a192dca993d07ec1 100644 (file)
--- a/docs/reference/gtk/migrating-3to4.xml
+++ b/docs/reference/gtk/migrating-3to4.xml
@@ -133,7 +133,7 @@
     <section>
       <title>Adapt to GtkWidget's size request changes</title>
       <para>
-        GTK+3 used five different virtual functions in GtkWidget to
+        GTK+ 3 used five different virtual functions in GtkWidget to
         implement size requisition, namely the gtk_widget_get_preferred_width()
         family of functions. To simplify widget implementations, GTK+4 uses
         only one virtual function, GtkWidgetClass::measure() that widgets
@@ -141,6 +141,22 @@
       </para>
     </section>
 
+    <section>
+      <title>Don't use symbolic colors in your CSS</title>
+      <para>
+        GTK+ 4 does not support @define-color and symbolic colors anymore.
+        We recommend that you use a css preprocessor like sass instead.
+      </para>
+    </section>
+
+    <section>
+      <title>Don't use -gtk-gradient in your CSS</title>
+      <para>
+        GTK+ now supports standard CSS syntax for both linear and radial
+        gradients, just use those.
+      </para>
+    </section>
+
   </section>
 
 </chapter>