Enabling Javascript in the webview Blocks

I  have been look everywhere on the net for how to enable javascript in webview but everything i find is code or logic no one actually show you how to do it in the blocks editor which is what we have to ultimately use.

Can someone upload how to actually do it in the blocks editor please? 

(My original issue is that i point the web view to my dating site but users can't upload pics from within my app, if you use a regular web browser it will let you uplaod here is a link to my apphttps://play.google.com/store/apps/details?id=appinventor.ai_key92kh.TLK)

Javascript is already enabled in the webviewer by default, and it does run javascript fine.

But it is no full browser. I imagine uploading an image using the webviewer probably won't work.

Where is the image coming from? Is it on the device's sd card?

Thanks for your reply... It would be fine if either could be accessed, but nothing is happening when the file button is pressed, when i access it in a real browser like firefox or chrome it go to the phones image gallery. This is what i would like to happen in my webview.