Dries Buytaert

Explanation

rel="shortlink" specifies a shorter URL for the current page, to be used in space constrained interfaces and/or for manual entry.

Some of the software used to generate or serve this page.

Some of the software used to generate or serve this page.

max-age specifies the maximum amount of seconds a page is considered valid. The higher max-age, the longer a page can be cached.
Notice A max-age of 60 seconds is short, especially if your content doesn't change frequently. Consider increasing max-age unless the URL has live updates.

This Expires date is in the future: the page can be served from a cache. The page is set to expire in 59 seconds. At that point, caches should be refreshed.
Notice Because there is a Cache-Control header with a max-age and/or s-maxage directive, the Expires header will be ignored. Consider removing Expires to save bandwidth and processing power.

The Strict-Transport-Security header (HSTS) instructs browsers to only use HTTPS for future connections to this domain, enhancing security by preventing downgrade attacks and cookie hijacking.
max-age specifies the time, in seconds, that the browser should remember to use HTTPS only for this domain.

This header enables the browser's built-in XSS protection. However, it's considered legacy and modern browsers may ignore it.
1 enables the browser's cross-site scripting (XSS) filtering.
mode=block instructs the browser to block the response if a XSS attack is detected, instead of sanitizing the page.
Notice While this header provides some protection, it's recommended to use Content-Security-Policy instead, as it offers more comprehensive and flexible protection against XSS and other injection attacks.

The X-Content-Type-Options header, when set to nosniff, prevents MIME type sniffing. This enhances security by ensuring browsers respect the declared Content-Type of the response, mitigating MIME confusion attacks.
The value nosniff is correctly set, providing protection against MIME type sniffing attacks.

X-Frame-Options prevents this URL from being embedded in an iframe. This protects against clickjacking attacks.
sameorigin means that this page can be displayed in a iframe, but only on the currrent origin. It can't be displayed on another domain. Consider setting this to deny for added security.

When a visitor navigates from one page to another page, browsers often pass along referrer information. The Referrer-Policy header controls how much referrer information a browser can share. This is important because private information can be embedded in the path or query string.
no-referrer-when-downgrade means that the protocol, host, port, path and query string are shared. It is only shared when the protocol security level remains the same (HTTP → HTTP, HTTPS → HTTPS) or improves (HTTP → HTTPS). When the protocol becomes less secure (HTTPS → HTTP), nothing is shared.

The Vary header specifies a list of headers that must be considered when caching responses. For a cached response to be used, these headers must match between the cached response and the new request. This ensures that the appropriate version of a resource is served based on factors like language, encoding, or device type.
Notice Varying on user-agent can lead to low cache efficiency due to the high number of unique user agents. Only use this if you're serving significantly different content based on user agent.

The type of the message body, specified as a MIME type.

The date and time at which the request was made. A browser uses it for age calculations rather than using its own internal date and time; e.g. when comparing against Max-Age or Expires.

missing Add a Content-Security-Policy header. The Content-Security-Policy header helps browsers prevent cross site scripting (XSS) and data injection attacks.

missing Add a Permissions-Policy header. Restrict access to device features like the camera, microphone, location, accelerometer and much more.

missing Add a Cross-Origin-Embedder-Policy to specify how this page can be loaded by cross-origin resources.

missing Add a Cross-Origin-Opener-Policy header to opt-in into better browser isolation.

missing Add a Cross-Origin-Resource-Policy header to specify who can load this page.

missing Add a X-Permitted-Cross-Domain-Policies header to prevent Flash, Adobe Reader and other clients from sharing data across domains.