Avoid downloading in the BG

[r3a1d3a1]

More and more websites are using fancy new Cloudflare protection mechanisms that require cookies to be sent and resource-sharing is limited to same-site, e.g. 500px.
Furthermore, high-quality pix can be bandwidth consuming, and re-downloading them in the background is certainly suboptimal.

So, how about changing CORS header 'onHeadersReceived' to * and accessing the images directly?
In the UI, a list of websites/domains where this happens could be specified, while warning the user about security implications of doing so. This way, hopefully the user would enable it only for websites with non-private images to minimize the risks of CORS * while getting around limitations of background-downloading.