Chat mode now shows an elapsed-seconds counter ("Stopping research… (Ns)") in the progress task line after the user clicks Stop, so it's clear the click registered even when the worker thread is blocked inside an LLM HTTP call (thinking-mode models like Qwen 3 and DeepSeek-R1 can take 30+ seconds to surface a stopping checkpoint because no chunks yield during ``<think>`` blocks). The counter only appears after 3 seconds elapsed — quick stops show the plain "Stopping research…" label without a number. The counter is cleared automatically whenever research stops, completes, or errors out. This is a UX-only mitigation; reducing the underlying termination latency would require deeper work such as per-token streaming or signal-based HTTP interruption.
