Feature: Add support for XEP-0444 Message Reactions

[marcellintacite]

Feature: Add support for XEP-0444 Message Reactions

Description

This PR implements XEP-0444: Message Reactions, allowing users to react to messages with emojis. It introduces a new plugin (reactions) that handles the UI for picking reactions, displaying them on messages, and managing the underlying XMPP stanza logic.

Key Changes

1. New Plugin: reactions

• Created a standalone plugin structure in src/plugins/reactions/.
• Implemented logic to parse incoming <reaction> elements from message stanzas.
• Implemented logic to send reaction stanzas with the correct XML namespace (urn:xmpp:reactions:0).
• Added optimistic UI updates (reactions appear immediately before server confirmation).

2. UI Components

• Reaction Picker (converse-reaction-picker):
  • Added a "Quick Actions" bar showing popular emojis (👍, ❤️, 😂, 😮).
  • Integrated a full emoji picker dropdown (lazy-loaded for performance).
  • Styled with glassmorphism effects to blend with the chat interface.
  • Uses CSS Anchor Positioning (with fallbacks) for robust dropdown placement.
• Message Bubbles:
  • Updated message templates to render reaction "pills" below messages.
  • Styled to resemble modern chat apps (Slack-like): rounded pills, hover effects, and active states.
  • Reactions are aggregated (e.g., "👍 3").
  • Clicking an existing reaction toggles it (edit your vote).

3. Technical Details

• Standard Compliance: Fully compliant with XEP-0444: Message Reactions.
• Styling: Reused existing emoji picker styles (src/shared/chat/styles/emoji.scss) to ensure consistency between the chat input and the reaction picker.

Screenshots / Video

emoji_converse.mp4

This still a Draft

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