WebStorage has been deprecated because, as far as I understand, it is no longer supported by the Chrome Web Store. However, it is still available if you right click on the add object popup and enable deprecated plugins. Keep a copy of the folder as well and, if one day in 5 years it is no longer shipped with c2, you can just paste it back into your plugins folder like any other 3rd party plugin.
Regarding the second point - almost certainly not a problem. There have been no bug reports I've been aware of where odd stuff has been happening because of that glitch.
So, do it!!