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+# MSC 2385: Disable URL Previews
+This MSC is an alternative suggestion to [MSC2376](https://github.com/matrix-org/matrix-doc/pull/2376).
+
+Currently URLs posted in chat give a URL preview. Sometimes, for example with bots, this can be
+unwanted. For instance if a bot is posting a message with a lot of links, or the content of the link
+is already obvious from the message itself.
+
+## Proposal
+This proposal adds a new, optional key to `m.room.message` messages, named `url_previews`. It is an
+array of strings containing the URLs a preview should be given to. If this key is absent, it is expected
+that the client gives URL previews for all URLs present in the message body. If a URL is present in this key that is *not*
+present in the body clients SHOULD NOT render a preview for that URL.
+
+### Examples
+No key added, preview to all URLs:
+```json
+{
+	"msgtype": "m.text",
+	"body": "Wow, check out this song! https://www.youtube.com/watch?v=oHg5SJYRHA0"
+}
+```
+
+Empty array for `url_previews`, thus no URL preview at all:
+```json
+{
+	"msgtype": "m.text",
+	"format": "or.matrix.custom.html",
+	"body": "Hey, look at what I did! [MSC2385: Disable URL Previews](https://github.com/matrix-org/matrix-doc/pull/2385)",
+	"formatted_body": "Hey, look at what I did! <a src=\"https://github.com/matrix-org/matrix-doc/pull/2385\">MSC2385: Disable URL Previews</a>",
+	"url_previews": []
+}
+```
+
+Array of URLs to preview, only those in the array are previewed:
+```json
+{
+	"msgtype": "m.text",
+	"body": "https://example.com https://matrix.org",
+	"url_previews": ["https://example.com"]
+}
+```
+
+## Potential issues
+URLs that should have a preview need to be sent twice - once in the body, once in `url_previews`. As
+this feature is meant for bots, normal human clients would probably omit `url_previews` alltogether,
+resulting in all URLs sent from them having a preview.
+
+URLs in `url_previews` and in the body need to match exactly, which could be confusing with trailing
+slashes (`/`).
+
+## Alternatives
+There could be an attribute added to the `<a>` tag which disables URL previews. See
+[MSC2376](https://github.com/matrix-org/matrix-doc/pull/2376).
+
+Instead of a whitelist there could also be a blacklist of URLs. However, as the likely scenario is a
+bot wanting to surpress all the previews for its URLs sent it seems like a whitelist is more appropriate
+here.
+
+## Security considerations
+You could get tricked more easily into being Rickroll'd. This can be alleviated by encouraging
+clients to request previews explicitly (either by hovering or by clicking a special button next to
+the link).