I spoke with Stanza team earlier today to exchange technical info about issues I and other users have been encountering, and how the calendar recently added could be contributing to it. We ran some performance tests of the site's load times with various combinations of MonkeyBroker and Stanza enabled and disabled. The conclusion we both reached was that StanzaCal itself had little to do with the latency issues. Much of the load / latency is due to the header bidding algorithms & concurrent refreshing done by theirs & Wowhead’s ad provider, Monkey Broker. The combination of the two sites' ad bidding algorithms was overtaxing the browser's capability to concurrently request resources, leading it to slow down, crash, or be in a near-constant state of loading.
As of now Stanza has switched away from Monkey Broker and Wowhead is already actively evaluating other ad partners (as stated in Site Stability Forum) that can meet revenue metrics while not heavily relying on anti-adblocking mechanisms or significantly impairing site performance. Switching off MonkeyBroker by Stanza should show some immediate improvement in overall site performance, and some technical solutions are being looked at to deliver the calendar to Premium users without ads.
This is in line with the longer term strategy that Wowhead will be adopting to improve performance. Specifically, users have expressed dissatisfaction with having ads autorefresh, and this will be one of the considerations taken in examining any new potential ad partners. Wowhead will need to keep using MonkeyBroker during the short term, but they recently have reduced the number of ads per page and auto-refreshing is turned off after a user has spent over an hour on the page
This isn’t an easy or quick problem to solve and the team will try its best to make periodic announcements with specific details to show progress. If you’d like to work with them closely around performance testing, please get in touch!
From me: I found the Stanza team very receptive to discussing technical details when I talked with them about ways site performance can be improved. They were very aware of and understanding of the community's concerns in various threads posted. I have been a vocal critic of how aggressive the ad model being used is, but I was very encouraged by the discussion and am newly hopeful that with their assistance we will be able to see some changes in the site performance soon.