after updating from 2.4.1 to latest version from github from
the following message could be found on lots of places:
Fatal error: Cannot use Piwik\Visualization\Config as Config because the name is already in use in /html/piwik/plugins/CoreVisualizations/Visualizations/HtmlTable/Goals.php on line 16
Please remove the file plugins/CoreVisualizations/Visualizations/HtmlTable/Goals.php. That file was moved in d0cb3453ba
Maybe you need to clean other files aswell...
perfect this solves it! thanks!