This link and the system menu screenshot provided basically the same
information: clarifying the context, so let's stick to the image that
doesn't require people to go to a different page.

Reusing that same image also makes sense as it displays the two buttons
that we are referring to.

Merge remote-tracking branch 'spriver/web/11385-update-shutdown-to-jessie' into web/11385-update-shutdown-to-jessie

Since we're breaking PO strings anyway, let's clean up a bit.

Merge remote-tracking branch 'spriver/feature/11243-OpenPGP-Applet-screenshots' into feature/11243-OpenPGP-Applet-screenshots

This reverts commit 99c1793b.

This reverts commit af5f8a22.

At least this is the case for me, and according to:

  https://support.mozilla.org/en-US/kb/keyboard-shortcuts-perform-firefox-tasks-quickly

Note: no content was changed! I tend to read the raw version of this
page a lot, so I like it pretty! :)

Fix-committed: #11799