Add documentation for config to skip widget_build_url for DM rooms (#…

…25518)

Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>

docs/config.md

@@ -320,7 +320,8 @@ The VoIP and Jitsi options are:
     }
     ```
     The `widget` is the `content` of a normal widget state event. The `layout` is the layout specifier for the widget being created,
-    as defined by the `io.element.widgets.layout` state event.
+    as defined by the `io.element.widgets.layout` state event. By default this applies to all rooms, but the behaviour can be skipped for DMs
+    by setting the option `widget_build_url_ignore_dm` to `true`.
 5. `audio_stream_url`: Optional URL to pass to Jitsi to enable live streaming. This option is considered experimental and may be removed
    at any time without notice.
 6. `element_call`: Optional configuration for native group calls using Element Call, with the following subkeys: