When trying the Page Activity (main wall) feature on regular user without rank this error showed up
[phpBB Debug] PHP Warning: in file [ROOT]/ext/pgreca/pgsocial/controller/main.php on line 328: Trying to access array offset on value of type null
[phpBB Debug] PHP Warning: in file [ROOT]/ext/pgreca/pgsocial/controller/main.php on line 329: Trying to access array offset on value of type null