repo-key.asc is the keyname from Matrix.org, which gets removed here:

Removed bad key C35EB17E1EAE708E6603A9B3AD0592FE47F0DF61 from /etc/apt/trusted.gpg

$ ls /usr/share/keyrings/matrix-archive-keyring.gpg
/usr/share/keyrings/matrix-archive-keyring.gpg

It's also removed with the keyring package.

$ sudo apt purge matrix-archive-keyring
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following package was automatically installed and is no longer required:
  linux-image-4.19.0-1-amd64
Use 'sudo apt autoremove' to remove it.
The following packages will be REMOVED:
  matrix-archive-keyring*
0 upgraded, 0 newly installed, 1 to remove and 16 not upgraded.
After this operation, 31.7 kB disk space will be freed.
Do you want to continue? [Y/n] y
(Reading database ... 130276 files and directories currently installed.)
Removing matrix-archive-keyring (2015.12.09+debian0.8) ...
(Reading database ... 130271 files and directories currently installed.)
Purging configuration files for matrix-archive-keyring (2015.12.09+debian0.8) ...
$ ls /usr/share/keyrings/matrix-archive-keyring.gpg
ls: cannot access '/usr/share/keyrings/matrix-archive-keyring.gpg': No such file or directory

That's managed by matrix-archive-keyring too with a yes/no question.

(on Debian and Ubuntu)

_Description: Trust this keyring in APT to verify data sources from anywhere?
 You may choose to enable matrix-archive-keyring as a system trusted keyring
 for the APT package management system, if you need it in place of the Debian
 archive in some situation.
 .
 Adding keyrings to APT's list of trusted keys is not necessary in most cases,
 and may be a risk for your system. Usually, it may be simply enough to use the
 "Signed-By" option described on the sources.list(5) manual page.

this is far-far better and makes far more sense.

Ended up with this.

I also just added a comment to the source it "exists mainly for Debian 8 (jessie) and Ubuntu 14.04 LTS (trusty), where the signed-by option is not supported."

(comment not seen in the description)

There is already debian/changelog and it should get installed by default?

I don't intend to do that sorry, because they are unreleased test builds. I also get a mix of versions and kept making changes without incrementing the version number.

For what it's worth, I've documented the changes as much as I remember in this room.

It will be nicer after +debian1, sure.

I also need to check out right now how to comply with Debian's Policy § 10.7.3 on config updates.

I'm using nheko. I've seen some beta versions.

nheko Reborn

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