[users@httpd] Apache 2.4.18 (Ubuntu 16.04): run user must be lock directory owner, or Apache falls back to default run user id

Hello, Apache: 2.4.18 (last available from Ubuntu 16.04 standard repository). If Apache run-time user (APACHE_RUN_USER var) is changed to anything but default (www-data, I am using Ubuntu), Apache lock directory (APACHE_LOCK_DIR var) should first be chown'ed by that new user, otherwise

[users@httpd] Apache 2.4.18: warnings issued since environment vars definitions isn't always loaded

Hello, OS: Ubuntu 16.04, Apache version: 2.4.18 (latest Apache from default repository). Command sudo apache2 -M writes spurious lines like this: [Wed Jan 18 03:32:29.510875 2017] [core:warn] [pid 11564] AH00111: Config variable ${APACHE_LOG_DIR} is not defined even though the mentioned