What is the problem?
There are two problems being fixed here:
1. When opening the composer, we are seeing multiple requests made to
the `/composer_messages` endpoint. This is due to our use of the
`transitionend` event on the `#reply-control` element. The event is
fired once for each transition event and the `#reply-control` element
has multiple transition events.
2. System tests have animations disabled so the `transitionend` event
does not fire at all.
What is the solution?
Instead of relying on the `transitionend` event, we can instead just
observer the `composerState` property of the `ComposerBody` component
and trigger the `composer:opened` appEvent with a delay that is similar
to the transition duration used for the `ComposerBody` component.
Responding to negative behaviour tends to solicit more of the same. Common wisdom states: "don't feed the trolls".
This change codifies that advice by introducing a new nudge when hitting the reply button on a flagged post. It will be shown if either the current user, or two other users (configurable via a site setting) have flagged the post.