Propose ability to do both "foreground" and "background" (code example attached)

[irvinm]

I think ideally people might want to either be able to configure foreground\background in a configuration OR be able to dynamically pick what they want based on the context menu. I modified background.js to test this out and this seems to work fairly well, but was unsure if you would even want it and\or how to branch and create a pull request.

I've attached background.js in a ZIP to discuss. [No JS attachments apparently]

background.zip

For me, I would prefer both options at the "root" level of the context menu, but I am not sure that is possible with web extensions.

[dcormier]

Given that Firefox's normal "View Image" context menu option opens the image in the foreground tab, this option doesn't seem necessary.