Just a PSA in case anyone else is careful with their context but sometimes wants to paste some long reply in the text entry part. Claude code (latest version, Claude Code v2.1.34 running Opus 4.6) will freeze if you type a long input (the limit is around 1,400 characters or so, about one very long paragraph.) You can test it reliably by typing more than this amount and it will freeze every time, losing the conversation history until that point.