Can browser extensions detect leaked secrets?

Yes, browser extensions can help detect suspicious secret-like patterns in frontend assets that are already reachable in the browser. But detection is limited to what the browser can access and what rules can sensibly surface.

What they can do well

• Observe shipped frontend assets
• Scan JavaScript bundles for suspicious patterns
• Preserve evidence in context

What they cannot do alone

• Prove exploitability automatically
• See server-side secrets that never reach the client
• Replace human validation and broader security testing