How to disable the 'embed_truncate' setting

I haven’t added any hosts to my site - I’m publishing posts with the wp-discourse plugin - but am still getting this:

I can see how this function could be useful for when a post excerpt is published through the wp-discourse plugin, but could there be a setting added to admin/site_settings/category/posting to make it possible to disable it for sites that are using the wp-discourse plugin to publish full posts to Discourse?