**Investigation**
~~We use `nonStallingEvaluateInExistingContext` as of today, which does
`eval()` inside (from our utilityScript) which breaks for some sites. It
causes a hang, since the returned `Promise` of `eval()` hangs. We don't
know as of today why this happens. Without wrapping it ini `eval()` it
does not hang.~~
~~Workaround: Do a plain Runtime.evaluate instead.~~
workaround: Only wait on main frame.
Relates https://github.com/microsoft/playwright/issues/28995 (keeping it
open until they confirm that it helps)
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