removed javascript "no thumbnail", now handling this in nginx

templates/macros.html

@@ -3,7 +3,7 @@
 	<a href="{{url_for('lecture', course=lecture.course.handle, id=lecture['id'])}}" title="{{ lecture.course.title }}" style="color: #000">
 		<div class="hidden-xs">
 			<div class="row">
-				<img class="col-xs-4" style="max-height: 120px; height: auto; width:170px" src="{{ config.VIDEOPREFIX }}/thumbnail/l_{{ lecture['id'] }}.jpg" alt="Vorschaubild" onerror="this.src='{{url_for('static',filename='no-thumbnail.png')}}'; this.onerror=''; ">
+				<img class="col-xs-4" style="max-height: 120px; height: auto; width:170px" src="{{ config.VIDEOPREFIX }}/thumbnail/l_{{ lecture['id'] }}.jpg" alt="Vorschaubild">
 				<div class="col-xs-4">
 					<span>{% if lecture.live %}<span class="label label-danger">Live</span> {% endif %}<strong>{{ lecture.course.short }}</strong>{% if ismod() %} <i>({{lecture.course_id}})</i>{% endif %}</span><br>
 					<span>{% if ismod() %}ID: {{lecture.id}}{% endif %}</span><br>
@@ -21,7 +21,7 @@
 		<div class="visible-xs">
 			<ul class="list-unstyled">
 				<li>
-					<img style="width: 100%;" src="{{ config.VIDEOPREFIX }}/thumbnail/l_{{ lecture['id'] }}.jpg" alt="Vorschaubild" onerror="this.src='{{url_for('static',filename='no-thumbnail.png')}}'; this.onerror=''; ">
+					<img style="width: 100%;" src="{{ config.VIDEOPREFIX }}/thumbnail/l_{{ lecture['id'] }}.jpg" alt="Vorschaubild">
 				</li>
 				<li>
 					{% if lecture.live %}<span class="label label-danger">Live</span> {% endif %}
@@ -168,7 +168,7 @@ $('#embedcodebtn').popover(
 {% macro lecture_list_item(lecture,videos,global_permissions) %}
 <li class="list-group-item" id="lecture-{{lecture.id}}">
 	<div class="row">
-		<div style="background-image: url('{{ config.VIDEOPREFIX }}/thumbnail/l_{{lecture.id}}.jpg')" class="col-sm-2 col-xs-12 thumbnailimg" onerror="this.src='{{url_for('static',filename='no-thumbnail.png')}}'; this.onerror=''; ">
+		<div style="background-image: url('{{ config.VIDEOPREFIX }}/thumbnail/l_{{lecture.id}}.jpg')" class="col-sm-2 col-xs-12 thumbnailimg">
 		{% if not videos|length is equalto 0 %}
 			<a href="{{url_for('lecture', course=lecture.course.handle, id=lecture.id)}}">
 				<span class="glyphicon glyphicon-play-circle playpreviewbtn"></span>