transaction script can't handle our site

We have a basic login check that works with WPM recorded test but not with a transaction script. When I look at the user agent string for the WPM test:

Mozilla/5.0 (Macintosh; Intel Mac OS X 12_2_1) AppleWebKit/537.36 (KHTML, like Gecko)
WPMRecorder/2020.2.6 Chrome/87.0.4280.141 Electron/11.3.0 Safari/537.36 PingdomTMS/2020.2

and compare it to the user agent of the transaction script:
Mozilla/5.0 (Unknown; Linux x86_64) AppleWebKit/534.34 (KHTML, like Gecko) PingdomTMS/0.8.5 Safari/534.34

I can see that the PingdomTMS versions are vastly different and I wonder if the latter needs to be brought up to date.

Here is another, public-accessible example:

And here is a transaction check that is designed to fail so that I can look at the screenshot:

Go to URL
Wait for element #doesnotexist to exist

The screenshot is attached, which shows the site isn't loading properly.