Checking with extensions in Chrome for security issues on websites.
In general:
Avast Online Security - Bitdefender's Traffic Light - Dr Web Link Checker (also out as an online service).
Netcraft Extension, Recx Security Analyzer, retire.js (no longer available as an online service), Quick Source Viewer, , VT4 browser extension, Zenmate Web Firewall (no longer available), just recently new: punkspider-browser-extension (also coming soon as an online service), Shodan, Tracker SSL.
Punkspider checks for SQLI, TRAV, XPATH and XSS vulnerabilities.
Also use this scan: (random example)
https://snyk.io/test/website-scanner/?test=210729_BiDcDR_4cd520c32268413a93d0db4d09dc1f4apolonus