HTTP Headers Analysis for https://css4j.github.io

Detected Technologies from Headers

See all in URL Inspect 3

Fastly

GitHub

Varnish

HTTP Security Headers

Status

Strict-Transport-Security

Present

max-age=31556952

Content-Security-Policy

Missing

Not configured Analyze

Content-Security-Policy-Report-Only

Missing

Not configured Analyze

X-Frame-Options

Missing

Not configured

X-Content-Type-Options

Missing

Not configured

Referrer-Policy

Missing

Not configured

Permissions-Policy

Missing

Not configured

Recommendations

• Increase HSTS max-age to at least 1 year and add includeSubDomains
• Add Content-Security-Policy header to prevent XSS attacks
• Add X-Frame-Options: DENY or SAMEORIGIN to prevent clickjacking
• Add X-Content-Type-Options: nosniff
• Add Referrer-Policy header (recommended: strict-origin-when-cross-origin)
• Consider adding Permissions-Policy to control browser features

Performance Headers

Accept-Ranges

Performance

bytes

Connection

Performance

close

Vary

Performance

Accept-Encoding

accept-ranges: bytes
connection: close
vary: Accept-Encoding

Caching Headers

Age

Caching

2

Cache-Control

Caching

max-age=600

Etag

Caching

"6abba924-14ef"

Expires

Caching

Fri, 02 Oct 2026 08:05:11 GMT

Last-Modified

Caching

Tue, 29 Sep 2026 12:03:48 GMT

age: 2
cache-control: max-age=600
etag: "6abba924-14ef"
expires: Fri, 02 Oct 2026 08:05:11 GMT
last-modified: Tue, 29 Sep 2026 12:03:48 GMT

Content Headers

Content-Length

Content

5359

Content-Type

Content

text/html; charset=utf-8

content-length: 5359
content-type: text/html; charset=utf-8

Server Headers

Server

GitHub.com

server: GitHub.com

CORS Headers

Access-Control-Allow-Origin

Cors

*

access-control-allow-origin: *

Cookies Headers

No cookies headers found

Other Headers

Date

Other

Fri, 02 Oct 2026 07:55:13 GMT

Via

Other

1.1 varnish

X-Cache

Other

HIT

X-Cache-Hits

Other

1

X-Fastly-Request-Id

Other

5027a8c2255b891bc3b50f6900b5090a82cb5adc

X-Github-Edge-Region

Other

iad

X-Github-Request-Id

Other

2824:17F162:85B003:8C5BD3:6ABF635F

X-Origin-Cache

Other

HIT

X-Proxy-Cache

Other

MISS

X-Served-By

Other

cache-ewr-kewr1740030-EWR

X-Timer

Other

S1790927714.965178,VS0,VE2

date: Fri, 02 Oct 2026 07:55:13 GMT
via: 1.1 varnish
x-cache: HIT
x-cache-hits: 1
x-fastly-request-id: 5027a8c2255b891bc3b50f6900b5090a82cb5adc
x-github-edge-region: iad
x-github-request-id: 2824:17F162:85B003:8C5BD3:6ABF635F
x-origin-cache: HIT
x-proxy-cache: MISS
x-served-by: cache-ewr-kewr1740030-EWR
x-timer: S1790927714.965178,VS0,VE2

Recommendations

Enable compression (gzip/brotli) to improve performance