BACK TO THE ORIGINAL TOPIC

To answer Rita's question, there are ad blockers that are apps, not Safari extensions. Generally they are a low level form of VPN (Virtual Private Network) that work outside of the browser to block or re-direct known advertising IP addresses and are often more effective than ad-blocking extensions.

SITE TEST RESULTS

Using Safari 11.1.2 I went to Rita's troublesome web site telwut.com and responded to a few of the "surveys". The site initially loaded very rapidly and when I selected a "survey" to respond to, it too loaded very rapidly. When I responded to a survey the response was uneven. Some surveys responded and displayed the survey results very quickly but others took several seconds to respond. In a second trail maybe ten minutes later everything was uniformly fast and responsive.

The uneven results leads me to suspect Telwut may be having server hardware or database software issues or is sensitive to site load (the number of simultaneous users) but there is no indication that Safari 11.1.2 or anything else on my end was causing a problem.

CONCLUSION

If Rita continues to experience significant slowdown on the site using her current version of Safari then:
  • There could be an issue with a Safari cache file.
  • There may have been a change in the site coding that her version of Safari does not handle well. (Updating to a more recent Safari would easily prove or disprove that.)
  • There is something else we are missing (Searching the console logs for Safari might turn up an indication there.)
which pretty well brings us back to where we started. 🤷‍♂️

If we knew what it was we were doing, it wouldn't be called research, would it?

— Albert Einstein