High CPU usage when not using Steam because it's still running the Store page in the web browser

[Dwedit]

I am seeing high CPU usage from SteamWebHelper when I'm not actively interacting with Steam in any way.

This is because even when all Steam windows are closed, it is still processing the web page for the Steam store, including all the animated elements.

One workaround is to go to the "Library" tab, which has no animations, so it has less CPU usage.

But Steam really should be closing or suspending the web browser when all Steam windows are closed.