[Changelog] RBI saml post support (#22387)

* Add initial changelog copy

* tweak copy a bit

* Update src/content/changelog/browser-isolation/2025-05-13-rbi-saml-post-support.mdx

Co-authored-by: Kate Tungusova <[email protected]>

---------

Co-authored-by: Chase Disher <[email protected]>
Co-authored-by: Kate Tungusova <[email protected]>

Author: cdisher

src/content/changelog/browser-isolation/2025-05-13-rbi-saml-post-support.mdx

@@ -0,0 +1,9 @@
+---
+title: SAML HTTP-POST bindings support for RBI
+description: Enable secure access to SSO-enabled applications in the remote browser.
+date: 2025-05-13
+---
+
+Remote Browser Isolation (RBI) now supports SAML HTTP-POST bindings, enabling seamless authentication for SSO-enabled applications that rely on POST-based SAML responses from Identity Providers (IdPs) within a Remote Browser Isolation session. This update resolves a previous limitation that caused `405` errors during login and improves compatibility with multi-factor authentication (MFA) flows.
+
+With expanded support for major IdPs like Okta and Azure AD, this enhancement delivers a more consistent and user-friendly experience across authentication workflows. Learn how to [set up Remote Browser Isolation](/cloudflare-one/policies/browser-isolation/setup/).