The two small screen icons at the top of the panel beside your chat switch between Compact view and Expanded view. Neither hides anything. Expanded view makes the panel wide and the conversation narrow, and it moves the message box out of its fixed position at the bottom of the window into the chat column itself. That is what makes it look as though the box has gone.
What each view does
- Compact view is the default. The conversation takes most of the width, the panel beside it is a fixed column, and the message box is pinned to the bottom of the window, where it stays put as you scroll.
- Expanded view swaps the two. The panel takes the space, and the conversation shrinks to the width the panel had. The box stops being pinned and sits at the foot of the chat column, so it scrolls with the conversation instead of floating over it.
Expanded view is for reading results. When the assistant has searched and the Results tab is full of project cards, a wide panel is the point of it.
Finding the box again
Scroll the chat column to the bottom. In Expanded view the box is the last thing inside that column rather than a bar across the window, so on a long conversation it sits below what you can currently see. Switching back to Compact view puts it back at the bottom of the window straight away.
The choice is not remembered
Every visit starts in Compact view. There is no setting for it, and changing it in one chat does not change it in another or on any other page.