Thread split view - escaping content edit closes thread

When editing a message in a thread in split view, attempting to cancel the message edit by using ESC (as suggested by the help text underneath the message being edited) collapses the entire thread. This does cancel the edit, but also requires finding and reopening the thread if you wanted to keep the thread open.

Editing in threads should require a second escape in order to close the thread. The first escape should only cancel the message edit.