Are you sure that this error is thrown by ruxitagent? This library is catching exceptions from other libraries and than throwing it again. Thanx of this it is able to send exception content to dynatrace, but there you will find detail where this was thrown originally.
Yes, sure ... its pretty obvious that its coming from that script when looking through the UI ... its the only script in the stack. And the thing its doing is probably related to performance stats for Dynatrace
What version of RUM Agent do you have? We have dynatrace across multiple clients and enviornments, users are using OSX and Safari in several versions. I've never seen such error, this is why I'm asking. If this happen on newest version of JS then you should rise support ticket.
since in the last year this post has been viewed quite often, we discussed this internally and I can give you the following answer to this.
According to our knowledge Safari in the past implemented the resource timings API but insufficiently, since they later removed it again. Since our way to capture resource timings works for IE, Chrome, and FF we believe that the error you experienced very likely occurred due to this insufficient implementation.
Nevertheless, we appreciate every stack trace that you can provide for us to dig deeper!