[Realmagnum]

Issue for this PR

Closes #60184

Type of change

• Bug fix
• New feature
• Refactor / code improvement
• Documentation

What does this PR do?

When adding multiple quotes or comment attachments to the composer (e.g. 5+ cards of 160px width), the cards are arranged in a single row with flex-nowrap inside a container styled with no-scrollbar. Once the cards exceed the composer width, they overflow past the right boundary and get clipped off, becoming invisible and unreachable.

This PR fixes the issue by:

• Replacing flex-nowrap overflow-x-auto with flex-wrap max-h-40 overflow-y-auto on data-slot="composer-attachments-scroll". Cards wrap cleanly onto multiple rows and can scroll vertically if they exceed ~3 rows.
• Removing the horizontal fade mask overlays and scroll-timeline animations in attachments.css that were masking cards at the horizontal edges.

How did you verify your code works?

• Verified with 5+ quote chips: cards wrap to row 2 and stay visible, clickable, and editable.
• Verified comment editor popover (QuoteCommentEditor) positions correctly on wrapped cards.
• Verified removing individual cards re-flows the remaining cards cleanly.

Checklist

• I have tested my changes locally
• I have not included unrelated changes in this PR

[opencodejr]

The change looks sound, but I couldn't check it visually. It's in the web/desktop composer and I had no browser here, so I reviewed the code, ran a type check on packages/app (passes) and ran the composer unit tests (all pass). The removed fade slots and scroll-timeline CSS aren't referenced anywhere else. QuoteCommentEditor positions itself from the card's on-screen position and re-measures on scroll, so it should follow cards on wrapped or scrolled rows.

Public API: unchanged.

For maintainers: this replaces the deliberate design (one horizontally scrolling row with edge fades) with wrapping rows. As the reply on #60184 notes, cards past the edge can currently be reached with a trackpad swipe or Shift+scroll, so this is a layout change to accept rather than a pure bug fix. With many attachments the composer can also grow up to about 160px taller.

@Realmagnum, could you add before/after screenshots (or a short video) with 5+ quote cards, ideally with one card's comment editor open on the second row?