Ctrl+B (background command) does nothing during the "thinking" phase, which looks identical to a running command

Ctrl+B only backgrounds an actively-running bash command, but a long thinking/generation phase shows a near-identical spinner. So when a command has already finished and Claude is still thinking, pressing Ctrl+B does nothing - a typed message just queues until the turn ends, making Ctrl+B feel like it randomly fails.

Concrete case from one of my sessions: a bash command finished in ~2s, but the spinner kept showing Billowing… (1m 7s · thinking some more). Pressing Ctrl+B during that did nothing, and my typed message stayed queued (Press up to edit queued messages) for ~45s until the turn finished.

Expected: a clear visual distinction between "running a command" (backgroundable with Ctrl+B) and "thinking" (not) - or some signal that there's nothing to background.

Environment: Claude Code 2.1.185, macOS.