wkwebview requiresUserActionForMediaPlayback not working

Question

i have a wkwebview that goes into youtube and I would like to click on a video without it automatically throwing me into the video player.

I tried stopping this in 3 different ways

1. using the config.requiresUserActionForMediaPlayback = true
2. in the decidePolicyForNavigationAction delegate function i check for the presence of a youtube video and set decisionHandler(WKNavigationActionPolicy.Cancel)
3. i also added a webView.stopLoading() to the stuff i did in #2

despite doing that, clicking on the link still triggers the video to automatically start playing.

i'm out of ideas; any thoughts?

i know i could try injecting some javascript but that seems like a last resort to me.