Am seeing the following issue in logstash.
Notice: Undefined index: pageprops in /srv/mediawiki/php-1.32.0-wmf.4/extensions/MobileFrontend/includes/api/ApiMobileView.php on line 149
Also seeing:
Warning: Invalid operand type was used: array_key_exists expects an array or an object; false returned. in /srv/mediawiki/php-1.32.0-wmf.4/extensions/MobileFrontend/includes/api/ApiMobileView.php on line 269
Warning: Invalid operand type was used: array_key_exists expects an array or an object; false returned. in /srv/mediawiki/php-1.32.0-wmf.4/extensions/MobileFrontend/includes/api/ApiMobileView.php on line 275
[{exception_id}] {exception_url} ErrorException from line 269 of /srv/mediawiki/php-1.32.0-wmf.4/extensions/MobileFrontend/includes/api/ApiMobileView.php: PHP Warning: Invalid operand type was used: array_key_exists expects an array or an object; false 7
[{exception_id}] {exception_url} ErrorException from line 275 of /srv/mediawiki/php-1.32.0-wmf.4/extensions/MobileFrontend/includes/api/ApiMobileView.php: PHP Warning: Invalid operand type was used: array_key_exists expects an array or an object; false
Possibly related to T192837 given the timing.