I did, but it installs Siril 0.9.10 while I expected 0.99.4:
$ sudo apt-get install siril
Reading package lists... Done
Building dependency tree
Reading state information... Done
Suggested packages:
gnuplot
The following NEW packages will be installed:
siril
0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded.
Need to get 0 B/1,260 kB of archives.
After this operation, 5,848 kB of additional disk space will be used.
debconf: delaying package configuration, since apt-utils is not installed
Selecting previously unselected package siril.
(Reading database ... 53221 files and directories currently installed.)
Preparing to unpack .../siril_0.9.10-2_amd64.deb ...
Unpacking siril (0.9.10-2) ...
Setting up siril (0.9.10-2) ...
Processing triggers for mime-support (3.62) ...
Processing triggers for hicolor-icon-theme (0.17-2) ...
Processing triggers for man-db (2.8.5-2) ...
Processing triggers for shared-mime-info (1.10-1) ...
Processing triggers for desktop-file-utils (0.23-4) ...
Also, when updating I get an error about the PPA’s signature:
$ sudo apt-get update
Hit:1 https://deb.debian.org/debian buster InRelease
Get:2 https://deb.debian.org/debian-security buster/updates InRelease [65.4 kB]
Get:3 http://ppa.launchpad.net/lock042/siril/ubuntu groovy InRelease [18.0 kB]
Ign:4 https://storage.googleapis.com/cros-packages/84 buster InRelease
Hit:5 https://storage.googleapis.com/cros-packages/84 buster Release
Err:3 http://ppa.launchpad.net/lock042/siril/ubuntu groovy InRelease
The following signatures couldn't be verified because the public key is not available: NO_PUBKEY A0F0E3D9922C071B
Reading package lists... Done
W: GPG error: http://ppa.launchpad.net/lock042/siril/ubuntu groovy InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY A0F0E3D9922C071B
E: The repository 'http://ppa.launchpad.net/lock042/siril/ubuntu groovy InRelease' is not signed.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.