WARNING: /opt/srv/www/htdocs/piwik_2.15.0/core/Filesystem.php(140): Warning - strpos() expects parameter 1 to be string, array given - Piwik 2.15.0

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WARNING: /opt/srv/www/htdocs/piwik_2.15.0/core/Filesystem.php(140): Warning - strpos() expects parameter 1 to be string, array given - Piwik 2.15.0 - Please report this message in the Piwik forums: http://forum.piwik.org (please do a search first as it might have been reported already)
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Thanks for the report, bug was created at Warning - strpos() expects parameter 1 to be string · Issue #9117 · matomo-org/piwik · GitHub