If you have trouble with scrolling history in Claude Code in tmux, try with env CLAUDE_CODE_NO_FLICKER=1. The variable is a bit of a misnomer. It changes the whole scrolling implementation to work much better inside tmux.
Somewhat annoying part of worktrees and Claude Code has been that you cannot resume or fork a session from a another worktree. claude-history now allows forking sessions from other projects (which worktrees technically are)