While unrelated to this, I would like browsers to suspend background tabs and maybe even compress their data and unload information that can be restored later (

While unrelated to this, I would like browsers to suspend background tabs and maybe even compress their data and unload information that can be restored later (for example, unload images from memory, drop JS bytecode and JIT caches). Majority of websites have no need to do anything when I am not watching them. Of course there are cases when you need some background activity, for example if you are listening to music or running a program. As I understand, it is extremely difficult do distuinguish between tabs doing useful work and not doing. I would be fine with a manual switch to allow site run in background.