Collabaora Online public key is not available

I have Collabora Online running in Ubuntu 20.04 (not a docker image) using the repo:
deb https://www.collaboraoffice.com/repos/CollaboraOnline/CODE-ubuntu2004 ./
I have the latest KeyRing installed.
When I update the repos I get this error:

Err:5 https://www.collaboraoffice.com/repos/CollaboraOnline/CODE-ubuntu2004 ./ InRelease
  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY D8915E456E7C440E

I have already checked the forum messages here and here and followed the update, but I still get the same error.

Should I be concerned?

hii @TheMetMan

Setting up and configuring native CODE packages on Linux

Collabora provide native Linux packages in deb and rpm formats. For the deb format 3 platforms are supported: amd64, ppc64, and arm64. For the rpm format only amd64 is supported.

1. Import the signing key:

CODE packages are digitally signed by Collabora Productivity Ltd. First step is to import the signing key.

On deb based distributions use the following command:

mkdir -p /etc/apt/keyrings && cd /etc/apt/keyrings sudo wget -O collaboraonline-release-keyring.gpg https://collaboraoffice.com/downloads/gpg/collaboraonline-release-keyring.gpg

On rpm based distributions use the following command:

wget https://www.collaboraoffice.com/repos/CollaboraOnline/CODE-rpm/repodata/repomd.xml.key && sudo rpm --import repomd.xml.key

2. Add CODE package repositories:

On deb based distributions create /etc/apt/sources.list.d/collaboraonline.sources with the following contents:

Types: deb URIs: Index of /repos/CollaboraOnline/CODE-deb Suites: ./ Signed-By: /etc/apt/keyrings/collaboraonline-release-keyring.gpg

On rpm based distributions use the following commands:

RHEL, CentOS, Fedora, etc.:

sudo yum-config-manager --add-repo Index of /repos/CollaboraOnline/CODE-rpm

SUSE:

sudo zypper ar ‘Index of /repos/CollaboraOnline/CODE-rpm’ ‘CODE’ sudo zypper mr -r ‘CODE’ # enable auto refresh

3. Install packages:

On deb based distributions use the following command:

sudo apt update && sudo apt install coolwsd code-brand

On RHEL, CentOS, Fedora, etc. use the following command:

sudo yum install coolwsd CODE-brand

On SUSE, use the following command:

sudo zypper ref && sudo zypper in coolwsd CODE-brand

This is the minimal installation, without localizations. For full installation install ‘collaboraoffice*’ packages.

4. Configuration:

Edit /etc/coolwsd/coolwsd.xml. Collabora Online (coolwsd) service runs via systemd. After editing the configuration file, you have to restart the service:

sudo systemctl restart coolwsd

Collabora Online logs into systemd journal by default. You can check the log with:

sudo journalctl -u coolwsd

The default configuration is looking for an SSL certificate and key, which are not present, so probably it’s the best to disable SSL, and optionally enable SSL termination, then set up the reverse proxy.

Thanks
Darshan