Copy icon truncates long assistant messages (cuts after first fenced code block)

Copy icon truncates long assistant messages

Environment: Claude Code VS Code extension, Windows 10, interactive session.

Symptom: Clicking the copy icon on a long assistant message copies only part of the
message to the clipboard. This has happened repeatedly across sessions, not a one-off.

Repro detail from one instance: the copied text stopped exactly at the point where the
first fenced code block ( `python ... ` ) in the message closed — 1,444 characters into
a much longer message. Everything after that closing fence was silently dropped from the
clipboard, even though the fence was mid-document, not near the end.

This suggests the copy handler may be capturing only the DOM range up through the first
code-block component rather than the full rendered message, rather than a raw character-count
cap (1.4KB is too small to be a length limit, and the message contained several KB more text
after the cut point).

Expected: copy icon copies the entire message body, regardless of how many fenced code
blocks it contains or where they fall.

Impact: any long or code-block-containing reply can't be reliably copied out of the chat
pane; content past the first code fence is silently lost with no error or indication that the
copy was incomplete.