What is definitely not okay is doing so without consent or informing the user, this applies doubly on mobile devices with limited bandwidth and battery.

The reality of it seems far different. What stops a site from running all the miners at once? They'll likely pick what produces the most returns and may never audit shady networks. Then there's the notion of me getting what I paid for. What stops a site from getting more from me than the content is 'worth' and pocketing that change? Multiply that by every site.

We may or may not agree that ad networks and their tactics are to blame for the current situation. We're also dealing with sites that are either complicit by ignorance and have never audited their content, or they're complicit by straight malice and just need their money however they can get it.

As a user that seemingly can't trust any of the players, I feel like Mozilla has my back. As a web developer, I have a blog with zero ads with the notion that if I can't afford the $5 vps it runs on, maybe I shouldn't produce said content. That doesn't hold very much water for most useful content producers though because at some point the cost of infrastructure becomes to much to handle.

I think ultimately I'd feel better about a 'browser blessed' mining network or set of standards or something more altruistic that somewhat like Patreon, showed me what I earn and let me distribute it how I see fit. It would be more akin to tipping culture in Europe over the US though, where I gave above the usual service and not guilt me into helping them make ends meet.