Calendar is not showing anymore

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7

Here is the full log of access log when I try to open the calendar:

217.8.58.12 - - [08/Dec/2016:17:47:30 +0100] "GET /index.php/apps/calendar/ HTTP/1.1" 200 11195 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
217.8.58.12 - - [08/Dec/2016:17:47:31 +0100] "GET /apps/calendar/js/vendor/fullcalendar/dist/fullcalendar.css?v=1cec7d9b0055fbec9f815488c35974e9 HTTP/1.1" 200 8463 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
217.8.58.12 - - [08/Dec/2016:17:47:31 +0100] "GET /apps/calendar/js/vendor/jquery-timepicker/jquery.ui.timepicker.css?v=1cec7d9b0055fbec9f815488c35974e9 HTTP/1.1" 200 1524 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
217.8.58.12 - - [08/Dec/2016:17:47:31 +0100] "GET /apps/calendar/css/public/app.css?v=1cec7d9b0055fbec9f815488c35974e9 HTTP/1.1" 200 5078 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
217.8.58.12 - - [08/Dec/2016:17:47:31 +0100] "GET /apps/calendar/l10n/de.js?v=1cec7d9b0055fbec9f815488c35974e9 HTTP/1.1" 200 4154 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
217.8.58.12 - - [08/Dec/2016:17:47:31 +0100] "GET /apps/calendar/js/vendor/jstzdetect/jstz.js?v=1cec7d9b0055fbec9f815488c35974e9 HTTP/1.1" 200 4807 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
217.8.58.12 - - [08/Dec/2016:17:47:31 +0100] "GET /apps/calendar/js/vendor/jquery-timepicker/jquery.ui.timepicker.js?v=1cec7d9b0055fbec9f815488c35974e9 HTTP/1.1" 200 15077 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
217.8.58.12 - - [08/Dec/2016:17:47:31 +0100] "GET /apps/calendar/js/vendor/ical.js/build/ical.js?v=1cec7d9b0055fbec9f815488c35974e9 HTTP/1.1" 200 59834 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
217.8.58.12 - - [08/Dec/2016:17:47:31 +0100] "GET /apps/calendar/js/vendor/angular-bootstrap/ui-bootstrap.js?v=1cec7d9b0055fbec9f815488c35974e9 HTTP/1.1" 200 53178 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
217.8.58.12 - - [08/Dec/2016:17:47:31 +0100] "GET /apps/calendar/js/vendor/angular-bootstrap/ui-bootstrap-tpls.js?v=1cec7d9b0055fbec9f815488c35974e9 HTTP/1.1" 200 56866 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
217.8.58.12 - - [08/Dec/2016:17:47:31 +0100] "GET /apps/calendar/js/vendor/fullcalendar/dist/locale-all.js?v=1cec7d9b0055fbec9f815488c35974e9 HTTP/1.1" 200 33793 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
217.8.58.12 - - [08/Dec/2016:17:47:31 +0100] "GET /apps/calendar/js/vendor/davclient.js/lib/client.js?v=1cec7d9b0055fbec9f815488c35974e9 HTTP/1.1" 200 3677 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
217.8.58.12 - - [08/Dec/2016:17:47:31 +0100] "GET /apps/calendar/js/vendor/hsl_rgb_converter/converter.js?v=1cec7d9b0055fbec9f815488c35974e9 HTTP/1.1" 200 1233 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
217.8.58.12 - - [08/Dec/2016:17:47:31 +0100] "GET /apps/calendar/js/vendor/fullcalendar/dist/fullcalendar.js?v=1cec7d9b0055fbec9f815488c35974e9 HTTP/1.1" 200 100527 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
217.8.58.12 - - [08/Dec/2016:17:47:31 +0100] "GET /apps/calendar/js/public/app.js?v=1cec7d9b0055fbec9f815488c35974e9 HTTP/1.1" 200 41369 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
217.8.58.12 - - [08/Dec/2016:17:47:31 +0100] "GET /apps/calendar/js/vendor/angular/angular.js?v=1cec7d9b0055fbec9f815488c35974e9 HTTP/1.1" 200 293979 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
217.8.58.12 - - [08/Dec/2016:17:47:31 +0100] "GET /index.php/core/js/oc.js?v=1cec7d9b0055fbec9f815488c35974e9 HTTP/1.1" 200 3395 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
217.8.58.12 - - [08/Dec/2016:17:47:31 +0100] "GET /apps/calendar/img/rightarrow.svg HTTP/1.1" 304 263 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
217.8.58.12 - - [08/Dec/2016:17:47:31 +0100] "GET /apps/calendar/img/leftarrow.svg HTTP/1.1" 304 263 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
217.8.58.12 - - [08/Dec/2016:17:47:32 +0100] "GET /apps/calendar/templates/colorpicker.html HTTP/1.1" 200 923 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
217.8.58.12 - - [08/Dec/2016:17:47:31 +0100] "GET /index.php/avatar/jurgenhaas/32 HTTP/1.1" 200 1907 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
217.8.58.12 - - [08/Dec/2016:17:47:32 +0100] "POST /index.php/apps/calendar/v1/config HTTP/1.1" 200 799 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
217.8.58.12 - - [08/Dec/2016:17:47:32 +0100] "GET /index.php/apps/calendar/v1/timezones/EUROPE/BERLIN.ics HTTP/1.1" 200 1193 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
217.8.58.12 - - [08/Dec/2016:17:47:32 +0100] "PROPFIND /remote.php/dav HTTP/1.1" 207 1538 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
217.8.58.12 - - [08/Dec/2016:17:47:34 +0100] "PROPFIND /remote.php/dav/principals/users/jurgenhaas/ HTTP/1.1" 207 1472 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"

Does that tell you anything?