I'm not sure if that would slow the page down and make it unusable though. Prioritizing non-mining activity seems like it might be trickier than simply capping processor usage.
Although it's not quite the same thing, it makes me think of how bandwidth heavy pages are now. Once upon a time, I browsed the web on 56K, or even 14.4K. Now, when my phone gets throttled to 128K many sites are unbearable.
If this problem persists, we will see tools popping up that use the OS APIs for restricting resource usage (e.g. cgroups on Linux) when starting the browser.
Although it's not quite the same thing, it makes me think of how bandwidth heavy pages are now. Once upon a time, I browsed the web on 56K, or even 14.4K. Now, when my phone gets throttled to 128K many sites are unbearable.