In my opinion, the significance of these options was still not super
clear. It wasn't obvious that the setting under Appearance will disable
them globally, and that the per-room option was discoverable.
Another change was using the term "Link preview" instead of "URL
preview", which is more common verbiage in chat applications other than
Element.
I re-arranged everything now so it makes more semantic sense, e.g. all
the message layout stuff is together in one card. I also made
bubble-only options hide themselves to reduce the amount of clutter
for compact layout users. Some small grammatical things were changed
like "Show Avatar" -> "Show Avatars".
