Inject CSS feature request

[gitgit3]

It would be nice to be able to add some CSS to the page easily.

I was using the Rust bindings briefly and there was a inject_css() function supplied. I have written a similar function for dlang which calls webview_eval() to run some JS which adds a <script> tag to the head of the document. I've stuck it in copy of package.d for now.

One problem I am having is that the document is not fully loaded when I call inject_css() and the JS ca fail. It is not clear to me how to block, or is there a way of getting a callback when the document has finished loading.

I can of course setup an onload() in the body tag but I'd rather set the callback in the webview API if possible rather that messing around with yet more JS. I feel that this functionality should be available out-of-the-box.

Thoughts/help appreciated.