When you select the smaller view mode, the button at the bottom right of the screen, your reply window is still full width, I'm guessing this wasn't intended.
I'd appreciate it if someone could move this to bugs section, I thought it would automatically post my reply there since I clicked back and into the bugs section while the reply window was still open 
@SupaHam I'd say that was intended behaviour, the read more link on latest widget is sometimes obscured by the button to change width. So if they both moved, you'd never get to that post. 
@a_5mith I'm not sure I fully understand, but do you think this is something that could be fixed in the future?
Excuse my ignorance, but what does that have to do with the issue I'm reporting? I'm reporting about the reply window being full width, not the button that changes the width of your view.
@SupaHam 
You're right. I misread your original post.
To actually answer your question, I'm not sure, as when the composer hits a certain width, it changes to a different preview mode, the composer is being reworked at some point, one of the devs said it was a stopgap between a more permenant solution.
@SupaHam said:
When you select the smaller view mode, the button at the bottom right of the screen,
Which button is this? There's no resize button there as far as I can see 
@julian http://s.supaham.com/pXHaGb.png the bottom right
@SupaHam I'm pretty sure that it was still intended to be full width, but someone correct me if I'm wrong.
Yep, the composer does not resize if that button is pressed.
