The 'Wide Chat Layout' setting toggles a 'wide-chat-layout' class on
the document root that widens '.chat-column' and '.chat-message-column'
from 48rem to 64rem, but '.chat-input-column' (which wraps the
textarea) was missing the matching rule, so the prompt input stayed
narrow while the messages above it widened.
Add the missing '.wide-chat-layout .chat-input-column { width:
min(100%, 64rem) }' selector so the input column tracks the message
column under the same setting.
Roberto Bertó
49bf1dbff3