iframe support?

I'm not sure if it's the problem, but it looks like iframes don't get rendered. I can't be sure because there is no DevTools but I see that iframes aren't there (which is a core part of my app).

Start by reproducing the report with an application that contains an iframe and verify whether the element is absent or simply not visible. The issue mentions no source files or tests, so inspect the webview rendering entry points and existing examples first; done means iframe content renders reliably.

Written by the indexing model from the issue text.