Security updates for Monday

Security updates have been issued by Arch Linux (chromium, firefox, mbedtls, nextcloud, python-pillow, ruby, ruby2.6, ruby2.7, systemd, thunderbird, varnish, and vivaldi), Debian (thunderbird), Fedora (chromium, firefox, and linux-firmware), Gentoo (apache, commons-fileupload, dovecot, and mediawiki), openSUSE (firefox, fossil, go1.16, and icinga2), Oracle (firefox, kernel, and kernel-container), Red Hat (nettle), and SUSE (firefox and go1.16).