Manual:$wgCookieSameSite

Cookies: $wgCookieSameSite
The SameSite cookie attribute used for login cookies.
Introduced in version:	1.34.3 (Gerrit change 608993; git #f8a7a1ac)
Removed in version:	Still in use
Allowed values:	`"Lax"`, `"Strict"`, `"None"` or an empty string/`null`
Default value:	`null` (gerrit:608993, gerrit:612335, gerrit:615843)
Other settings: Alphabetical \| By function

Details

This only applies to login cookies, since the correct value for other cookies depends on what kind of cookie it is.

SameSite=None is only permitted for HTTPS requests. See $wgForceHTTPS ).

This variable was added in MediaWiki 1.35.0 (gerrit:608993).

It was backported to 1.34 as part of the MediaWiki 1.34.3 release (gerrit:612335).

It was also backported to 1.31 as part of the MediaWiki 1.31.9 release (gerrit:618543).