security.txt file detector by Olivier Debré

The extension aims at helping ethical hackers to check easily and quickly if a website publishes a security.txt file (cf. RFC 9116 A File Format to Aid in Security Vulnerability Disclosure).
It does so by:
- showing a red (no such file) or green icon (file present);
- displaying its content.
Caveat: When a [root directory]/.well-known/security.txt file exists, its content is displayed without any syntax check.