Answer
Direct and group People chats collapse long text. An AI reply initially shows one rich preview, such as a link, image, map, file or audio player. Show Full Message expands its text and hidden previews together; Hide Full Message restores the preview. The control sits above the reply-to card.
An illustrated reply starts with its first illustrated section and one image. Separate image-search galleries keep their own gallery and viewer. People chats also fold checklists after four items, including forwarded lists, and polls after four choices. Private AI and Temporary Chat timelines show the full text, although search results can still expand. In the updated apps, an AI answer you requested stays fully open while you remain in the chat; after you leave and return, it folds like other long messages. Everyone else sees the folds.
Expansion first brings the message’s beginning into view where possible. Scrolling yourself cancels automatic positioning, and reduced motion makes it immediate. Previews that arrive later do not shorten text you are already reading. Audio previews keep the usual text allowance; larger rich previews may show a shorter excerpt.