Steps to reproduce

1. Open the page
   https://freedium.cfd/https://mychen76.medium.com/revolutionizing-code-agents-with-multi-million-token-model-new-agentic-workflow-prompts-memory-141b3fc2c284
2. Click "Configure site" popup menu on the tab

Actual behavior

mychen76.medium.com configuration is open

Expected behavior

freedium.cfd configuration should be open

System

macOS 15.5

Firefox version

140.0esr

Sidebery version

5.3.3

Logs