Manual:$wgNewPasswordExpiry

Email settings: $wgNewPasswordExpiry
The time, in seconds, after which an emailed temporary password expires.
Introduced in version:1.15.0
Removed in version:still in use
Allowed values:(integer)
Default value:3600 * 24 * 7 (7 days)

Details edit

The time, in seconds, after which an emailed temporary password expires.

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