The plugin SpreadMenus by VDigital is now integrated in the core. That involves that themes creators must not integrate code from this plugin. This evolution also asks minor css changes in some themes (margin-left mainly).
The “Lost Password” feature was rewritten from scratch. Themes which overwrite password.tpl must take the new file into account. This is not a minor rewrite, so please at least remove password.tpl from your theme as long as you don't make it compliant with Piwigo 2.3.
In password.tpl, there is only one trigger on the content of the email sent with the new password: