Messages sent by muted users are hidden. To make sure they are
displayed properly, we provide them a HTML structure similar to
that of a normal message so that any CSS applied to a normal
message also applied to it.
This fixes message controls being misaligned in hidden message.
* We show a "Click here to reveal." hyperlink in the hidden
message dialog for user to click on and read a hidden message.
* The "reveal" action is temporary, in the sense that a revealed
message will again be hidden once the broswer tab reloads or
if the user renarrows.
* When a message is revealed, we make sure to show the sender
of that message, even if it isn't the first message of it's group.
This is because the first message of that message group (which
would have otherwise shown the sender) can still be hidden.
* Reactions and background color after revealing a message are
the same as if the message hadn'e been hidden at all in the
first place.
* We hide the sender and reactions on messages sent by muted
users, and replace the content with a "This message was hidden"
dialog.
* Ideally, we should collapse a series of consequetive
messages sent by muted users into one such dialog, but
that could break the cursor behaviour and `near/<message_id`
links, so we as of now show one dialog per muted message.
* Because we hide the sender, there is a chance of the first
hidden message in a group looking like it was sent by the
author of the message above it. To tackle this, we intentionally
make the hidden message dialog float-left, so that it is clear
that this is a special type of message.
* For context, we still show the timestamp of the message.
* Starring, editing, deleting etc a message still work just like
before.
A further commit will add the ability to reveal a
hidden message.
Aman Agrawal
Abhijeet Prasad Bodas