AdBlocker Ultimate does not require a license key for its standard browser extension, as it is a free and open-source tool.
About AdBlocker Ultimate:
Another angle: maybe they want to support the developer but still think the full version is too expensive. Explaining the value of legitimate ad blockers and how free alternatives work could help. Also, suggesting alternatives like uBlock Origin or Brave browser's built-in ad blocker might be useful. Adblocker Ultimate License Key Free
Benefits of Using Adblocker Ultimate: