#msgs .bubble had a blanket user-select:none (added to suppress iOS's long-press
magnifier), which also blocked mouse text-selection on desktop. Scope the
none to touch devices only (@media (hover:none)); keep it in multi-select mode.
Desktop can now highlight/copy message text. Verified: desktop=auto,
touch=none, sel-mode=none.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>