TBB shows HTTPS Everywhere popup

When you start TBB for the first time, you'll get a fade-in popup up below the url bar. Saying:

HTTPS Everywhere is now active. You can toggle it on a site-by-site basis by clicking the icon in the address bar.

And when you close it, it opens https://www.eff.org/https-everywhere/faq.

This might be ok for users who installed HTTPS Everywhere manually into Firefox, but when it comes bundled with TBB, this message is confusing.

Please disable this fade-in popup by default. You did a similar thing in legacy/trac#5300 (closed) already.