Clicking Copy repeatedly makes the button label flicker #49

Context

js/copy-code.js sets the label to "Copied" and schedules a setTimeout to put it back after 1600ms. Clicking again before that fires schedules a second timer while the first is still pending, so the label reverts early and can flicker between states.

What to change

Files: js/copy-code.js

Requirements:

• Keep a reference to the pending timer and clear it before starting a new one
• Rapid clicks should mean the label stays "Copied" for the full period after the last click
• Per button — one block's timer must not affect another's
• Do not introduce a global; the existing code is an IIFE per block for a reason

Acceptance criteria

• Clicking five times quickly leaves "Copied" showing for the full duration after the last click
• No flicker
• Two different code blocks behave independently
• The clipboard still receives the right text

How to verify locally

Open any page with code blocks and click one Copy button five times in a second.

python3 -m http.server 8000

Then open http://localhost:8000.

Difficulty

Intermediate. A small, satisfying bug with a clear reproduction.

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