This allows for more flexibility in configuring which media URLs will
automatically render and which media URLs may be manually rendered by
the user (via the message actions dropdown).
For example, suppose you want to automatically render all media URLs
from https://xmpp.org, but still allow other media (which won't render
by default) to be rendered manually by the user (by clicking the "Show
URL previews" message dropdown action).
In this case, you set `render_media` to `['xmpp.org']` and
`allowed_image_domains` to `null` or `undefined`.
Or if you want to automatically render images from xmpp.org, and
restrict the domains users might manually click to render, you can add
those extra domains to `allowed_image_domains`.
It's now necessary to add a `converse-root` element in the DOM where you
want Converse to render (previously it was any element with the id
`#conversejs`).
Also, turned `converse-chats` element into a Lit element and re-render
`converse-root` and `converse-chats` when the `view-mode` or `singleton`
settings change. This is a step towards being able to change the view
mode on the fly and have the entire chat re-render appropriately.
Fixes#2647
even if the global configuration is to disallow it.
* When parsing, include all media URLs, not just the ones from allowed domains.
That makes it possible to change allowed domains on-the-fly,
while still allowing media in individual messages to be shown manually
(via the message actions dropdown).
* Merge `embed_audio`, `embed_video` and `show_images_inline` into `render_media`
* Create new config settings for allowable domains for images, video and audio
* Check the URL domain against a whitelist for the message actions dropdown
