MediaWiki:Common.css

Note: After publishing, you may have to bypass your browser's cache to see the changes.

Firefox / Safari: Hold Shift while clicking Reload, or press either Ctrl-F5 or Ctrl-R (⌘-R on a Mac)
Google Chrome: Press Ctrl-Shift-R (⌘-Shift-R on a Mac)
Edge: Hold Ctrl while clicking Refresh, or press Ctrl-F5.

#ca-history {
    display: none !important;
}

#p-tb {
    display: none !important;
}
<head>
    <meta name="google-adsense-account" content="ca-pub-9623793068560892">
</head>