Get rid of the registry for now

it should just be a proposal. We can add the registry later.

README.rst

@@ -25,12 +25,10 @@ Structure of this repository
   contained in the specification, along with example JSON files.
 - ``meta``: documents outlining the processes involved when writing
   documents, e.g. documentation style, guidelines.
-- ``registry``: Lists of identifiers for use in various parts of the Matrix protocol.
 - ``scripts``: scripts to generate formatted versions of the
   documentation, typically HTML.
 - ``specification``: the specification split up into sections.
 
-
 .. _OpenAPI: https://github.com/OAI/OpenAPI-Specification/blob/master/versions/2.0.md
 .. _JSON Schema: http://json-schema.org/
 
@@ -68,7 +66,7 @@ The above will write the rendered version of the specification to
 
 Windows users
 ~~~~~~~~~~~~~
-The ``source`` program does not exist on Windows, so instead run one of the
+The ``source`` program does not exist on Windows, so instead run one of the 
 ``activate`` files in ``.\env\Scripts\`` to activate the virtual environment.
 
 If you're on Windows Vista or higher, be sure that the "Symbolic Links"

proposals/2858-Multiple-SSO-Identity-Providers.md

@@ -84,9 +84,11 @@ of an object with the following fields:
    "Common namespaced identifier grammar" as defined in
    [MSC2758](https://github.com/matrix-org/matrix-doc/pull/2758).
 
-   A registry of brand identifiers is maintained at
-   [`matrix-doc/registry/m.login.sso_brand.md`](../registry/m.login.sso_brand.md). Contributors
-   are encouraged to add more brands to the registry.
+   To reduce confusion over which indentifier should be used for each brand
+   (for example: should "Sign in with Microsoft" be `com.microsoft` or
+   `com.azure`?), it is proposed to maintain a registry of identifiers outside
+   the core specification document, avoiding the need for a full MSC to add
+   entries to the list. An initial list of proposed identifiers is given below.
 
    Server implementations are free to add additional brands, though they should
    be mindful of clients which do not recognise any given brand.
@@ -122,6 +124,35 @@ SSO flow option without any `identity_providers` as there is no method for
 a client to choose an IdP within that flow at this time nor is it as
 essential.
 
+### Proposed initial identifiers for the `brand` indentifier
+
+ * Identifier: `com.apple`
+
+   Description: "Sign in with Apple". See
+   https://developer.apple.com/design/human-interface-guidelines/sign-in-with-apple/overview/buttons/.
+
+ * Identifier: `com.facebook`
+
+   Description: "Continue with Facebook". See
+   https://developers.facebook.com/docs/facebook-login/web/login-button/.
+
+ * Identifier: `com.github`
+
+   Description: Logos available at https://github.com/logos.
+
+ * Identifier: `com.gitlab`
+
+   Description: Login in via the hosted https://gitlab.com SaaS platform.
+
+ * Identifier: `com.google`
+
+   Description: "Sign in with Google". See
+   https://developers.google.com/identity/branding-guidelines.
+
+ * Identifier: `com.twitter`
+
+   Description: "Log in with Twitter". See
+   https://developer.twitter.com/en/docs/authentication/guides/log-in-with-twitter#tab1.
 
 ## Alternatives
 

registry/m.login.sso_brand.md

@@ -1,59 +0,0 @@
-# `m.login.sso` `brand` identifier registry
-
-The following is a list of identifiers for use in the optional `brand` field of the
-`identity_providers` property of the response to the [`GET /_matrix/client/r0/login`
-endpoint](https://matrix.org/docs/spec/client_server/latest#get-matrix-client-r0-login).
-
-This field was originally proposed in
-[MSC2858](https://github.com/matrix-org/matrix-doc/pull/2858).
-
-Links to other organisations' branding guidelines are provided on an
-informational basis, to help client developers understand the expected
-behaviour. No guarantee is given as to their accuracy, and each client author
-remains responsible for maintaining their application according to the latest
-best practices.
-
-## Assignments
-
-<!--
-Note that the following list is alphabetical by identifier - please keep it
-that way!
--->
-
- * Identifier: `com.apple`
- 
-   Description: "Sign in with Apple". See
-   https://developer.apple.com/design/human-interface-guidelines/sign-in-with-apple/overview/buttons/.
-   
- * Identifier: `com.facebook`
- 
-   Description: "Continue with Facebook". See
-   https://developers.facebook.com/docs/facebook-login/web/login-button/.
-   
- * Identifier: `com.github`
- 
-   Description: Logos available at https://github.com/logos.
-   
- * Identifier: `com.gitlab`
-
-   Description: Login in via the hosted https://gitlab.com SaaS platform.
- 
- * Identifier: `com.google`
-
-   Description: "Sign in with Google". See
-   https://developers.google.com/identity/branding-guidelines.
-   
- * Identifier: `com.twitter`
-   
-   Description: "Log in with Twitter". See
-   https://developer.twitter.com/en/docs/authentication/guides/log-in-with-twitter#tab1.
-
-
-## Requesting updates to the list
-
-Members of the community wishing to add new brands to this list are encouraged
-to open a pull request to update the list.
-
-Contributors are reminded that identifiers for the `brand` field should follow
-the [common textual identifier
-grammar](https://github.com/matrix-org/matrix-doc/blob/rav/proposals/textual_identifier_grammar/proposals/2758-textual-id-grammar.md).