If you see an error message saying "This app does not comply with Google's secure browser" while trying to open a link in a messenger app, it means that the way that particular app shows web pages is not safe to Google's standards.

This can happen, for instance, where messenger apps like Facebook Messenger, Instagram or Whatsapp open links an embedded web view.
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To avoid any potential security problems, we recommend that you try to open the link in a regular web browser instead. This will ensure a safer browsing experience and protect your device and personal information.