I\'m aware that if we use a iFrame in HTML we\'ve to sandbox it & add the \'allow-scripts\' permission to be true.
But my problem is I don\'t have a iFrame at all
For Jenkins hosted on Ubuntu:
put to /etc/default/jenkins
JAVA_ARGS="${JAVA_ARGS} -Dhudson.model.DirectoryBrowserSupport.CSP=\"\" "
visit http://
(about this and other options: https://wiki.jenkins.io/display/JENKINS/Features+controlled+by+system+properties)
UPD: this time when I did this the visiting /safeRestart was not enough. I had to do sudo service jenkins restart.