update-manager fails when executed as root

[Anirban D Incredible]

Ubuntu release and version:
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# cat /etc/*release*
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=20.04
DISTRIB_CODENAME=focal
DISTRIB_DESCRIPTION="Ubuntu 20.04 LTS"
NAME="Ubuntu"
VERSION="20.04 LTS (Focal Fossa)"
ID=ubuntu
ID_LIKE=debian
PRETTY_NAME="Ubuntu 20.04 LTS"
VERSION_ID="20.04"
HOME_URL="https://www.ubuntu.com/"
SUPPORT_URL="https://help.ubuntu.com/"
BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
VERSION_CODENAME=focal
UBUNTU_CODENAME=focal

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Budgie version:
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# budgie-desktop --version
budgie-desktop 10.5.1
Copyright © 2014-2019 Budgie Desktop Developers

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Current user
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# whoami
root

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Bug encountered:
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# update-manager
Unable to init server: Could not connect: Connection refused
Unable to init server: Could not connect: Connection refused
WARNING:root:can not import unity GI Namespace Dbusmenu not available
Unable to init server: Could not connect: Connection refused

(update-manager:4914): Gtk-WARNING **: 10:58:05.703: cannot open display:

[Anirban D Incredible (q2anirban)]

This is the latest version of Ubuntu Budgie, and also up to date on all packages. I am still experiencung the problem.
why do you think, it no longer affects Ubuntu Budgie?