Please take a look at the following message , is this a bug?
There is an error. Please report the message (Piwik 2.2.0) and full backtrace in the Piwik forums (please do a Search first as it might have been reported already!).
Warning: htmlspecialchars(): Invalid multibyte sequence in argument in /var/www/html/Cobo/piwik/vendor/twig/twig/lib/Twig/Extension/Core.php on line 971
Backtrace -->
#0 Piwik\Error::errorHandler(…) called at [:]
#1 htmlspecialchars(…) called at [/var/www/html/Cobo/piwik/vendor/twig/twig/lib/Twig/Extension/Core.php:971]
#2 twig_escape_filter(…) called at [/var/www/html/Cobo/piwik/tmp/templates_c/ae/0b/f0f1f85b2b6b914f42868cde5716b8cf99bc5b23cdf7bb5d665a841ce963.php:203]
#3 __TwigTemplate_ae0bf0f1f85b2b6b914f42868cde5716b8cf99bc5b23cdf7bb5d665a841ce963->doDisplay(…) called at [/var/www/html/Cobo/piwik/vendor/twig/twig/lib/Twig/Template.php:278]
#4 Twig_Template->displayWithErrorHandling(…) called at [/var/www/html/Cobo/piwik/vendor/twig/twig/lib/Twig/Template.php:252]
#5 Twig_Template->display(…) called at [/var/www/html/Cobo/piwik/vendor/twig/twig/lib/Twig/Template.php:263]
#6 Twig_Template->render(…) called at [/var/www/html/Cobo/piwik/vendor/twig/twig/lib/Twig/Environment.php:292]
#7 Twig_Environment->render(…) called at [/var/www/html/Cobo/piwik/core/View.php:246]
#8 Piwik\View->renderTwigTemplate(…) called at [/var/www/html/Cobo/piwik/core/View.php:241]
#9 Piwik\View->render(…) called at [/var/www/html/Cobo/piwik/plugins/Live/Controller.php:78]
#10 Piwik\Plugins\Live\Controller->render(…) called at [/var/www/html/Cobo/piwik/plugins/Live/Controller.php:115]
#11 Piwik\Plugins\Live\Controller->getLastVisitsStart(…) called at [:]
#12 call_user_func_array(…) called at [/var/www/html/Cobo/piwik/core/FrontController.php:505]
#13 Piwik\FrontController->doDispatch(…) called at [/var/www/html/Cobo/piwik/core/FrontController.php:85]
#14 Piwik\FrontController->dispatch(…) called at [/var/www/html/Cobo/piwik/core/dispatch.php:34]
#15 require_once(…) called at [/var/www/html/Cobo/piwik/index.php:47]
Thanks,
Henry