Upgraded from 2.0.3 to Piwik 2.3.0 , Error when using "Open row evolution" (no replies)

There is an error. Please report the message (Piwik 2.3.0) and full backtrace in the Piwik forums (please do a Search first as it might have been reported already!).

Notice: Uninitialized string offset: 0 in /apps/bweb/sites/piwik/htdocs/piwik/plugins/CoreHome/DataTableRowAction/RowEvolution.php on line 89

Backtrace -->

#0 Piwik\Error::errorHandler(...) called at [/apps/bweb/sites/piwik/htdocs/piwik/plugins/CoreHome/DataTableRowAction/RowEvolution.php:89]
#1 Piwik\Plugins\CoreHome\DataTableRowAction\RowEvolution->__construct(...) called at [/apps/bweb/sites/piwik/htdocs/piwik/plugins/CoreHome/Controller.php:161]
#2 Piwik\Plugins\CoreHome\Controller->makeRowEvolution(...) called at [/apps/bweb/sites/piwik/htdocs/piwik/plugins/CoreHome/Controller.php:127]
#3 Piwik\Plugins\CoreHome\Controller->getRowEvolutionPopover(...) called at [:]
#4 call_user_func_array(...) called at [/apps/bweb/sites/piwik/htdocs/piwik/core/FrontController.php:500]
#5 Piwik\FrontController->doDispatch(...) called at [/apps/bweb/sites/piwik/htdocs/piwik/core/FrontController.php:85]
#6 Piwik\FrontController->dispatch(...) called at [/apps/bweb/sites/piwik/htdocs/piwik/core/dispatch.php:34]
#7 require_once(...) called at [/apps/bweb/sites/piwik/htdocs/piwik/index.php:47]