docs: update migration guide to reflect removal of SockJS support

bjohansebas · bjohansebas · commit 847d2ed1927e · 2026-01-14T19:19:50.000-05:00
diff --git a/migration-v6.md b/migration-v6.md
@@ -2,6 +2,10 @@
 
 This document serves as a migration guide for `webpack-dev-server@6.0.0`.
 
+## ⚠ Breaking Changes
+
+- Support for **SockJS** in the WebSocket transport has been removed. Now, only **native WebSocket** is supported, or **custom** client and server implementations can be used.
+
 ## Deprecations
 
 - The static methods `internalIP` and `internalIPSync` were removed. Use `findIp` instead.
