PerformanceMonitor Error (no replies)

There is an error. Please report the message (Piwik 2.7.0) and full backtrace in the Piwik forums (please do a Search first as it might have been reported already!).

Strict Notice: Non-static method Piwik\Plugins\PerformanceMonitor\Tasks::getMaxVisits() should not be called statically, assuming $this from incompatible context in /var/customers/webs/mt1/xxx/piwik/mt/plugins/PerformanceMonitor/PerformanceMonitor.php on line 66

Backtrace -->

#0 Piwik\Error::errorHandler(...) called at [/var/customers/webs/mt1/xxx/piwik/mt/plugins/PerformanceMonitor/PerformanceMonitor.php:66]
#1 Piwik\Plugins\PerformanceMonitor\PerformanceMonitor->install(...) called at [/var/customers/webs/mt1/xxx/piwik/mt/core/Plugin/Manager.php:984]
#2 Piwik\Plugin\Manager->executePluginInstall(...) called at [/var/customers/webs/mt1/xxx/piwik/mt/core/Plugin/Manager.php:1105]
#3 Piwik\Plugin\Manager->installPluginIfNecessary(...) called at [/var/customers/webs/mt1/xxx/piwik/mt/core/Plugin/Manager.php:436]
#4 Piwik\Plugin\Manager->activatePlugin(...) called at [/var/customers/webs/mt1/xxx/piwik/mt/plugins/CorePluginsAdmin/Controller.php:394]
#5 Piwik\Plugins\CorePluginsAdmin\Controller->activate(...) called at [:]
#6 call_user_func_array(...) called at [/var/customers/webs/mt1/xxx/piwik/mt/core/FrontController.php:577]
#7 Piwik\FrontController->doDispatch(...) called at [/var/customers/webs/mt1/xxx/piwik/mt/core/FrontController.php:86]
#8 Piwik\FrontController->dispatch(...) called at [/var/customers/webs/mt1/xxx/piwik/mt/core/dispatch.php:34]
#9 require_once(...) called at [/var/customers/webs/mt1/xxx/piwik/mt/index.php:46]