Opening Side Panel with `tabId` parameter opens side panel on all tabs

Author: belthaZornvCreated Jun 10, 2024Updated Aug 17, 2025

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Describe the bug

I'm using:

https://github.com/GoogleChrome/chrome-extensions-samples/blob/main/functional-samples/cookbook.sidepanel-open/script.js

But the sidepanel stays open for all the tabs.

To Reproduce Steps to reproduce the behavior, or file the issue is found in:

  1. Go to 'cookbook'
  2. Copy and paste the code to your code (background script)
  3. Install and open sidePanel -> sidePanel on all tabs.

Expected behavior

SidePanel only open for the active tab

Screenshots If applicable, add screenshots to help explain your problem.

Notes Anything additional here.

Source: GoogleChrome/chrome-extensions-samples