Comment 49 for bug 2039873

This was verified on Mantic with -proposed (1:5.0.1-0ubuntu8~23.10.1). Here's how:

$ lxc launch ubuntu-daily:23.10 c2
Creating c2
Starting c2

$ lxc shell c2

root@c2:~# apt-get update
...
root@c2:~# apt-get install -Vy liblxc-dev
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
The following additional packages will be installed:
...
   liblxc-common (1:5.0.1-0ubuntu7)
   liblxc1 (1:5.0.1-0ubuntu7)
...
   lxcfs (5.0.3-1)
..

root@c2:~# dpkg -l | grep liblxc-dev
ii liblxc-dev 1:5.0.1-0ubuntu7 amd64 Linux Containers userspace tools (development)
root@c2:~# grep LXC_DEVEL /usr/include/lxc/version.h
#define LXC_DEVEL 1

# enable -proposed

root@c2:~# apt-get update
...
root@c2:~# apt-get install -t mantic-proposed -Vy liblxc-dev
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
The following additional packages will be installed:
   liblxc-common (1:5.0.1-0ubuntu8~23.10.1)
   liblxc1 (1:5.0.1-0ubuntu8~23.10.1)
The following packages will be upgraded:
   liblxc-common (1:5.0.1-0ubuntu7 => 1:5.0.1-0ubuntu8~23.10.1)
   liblxc-dev (1:5.0.1-0ubuntu7 => 1:5.0.1-0ubuntu8~23.10.1)
   liblxc1 (1:5.0.1-0ubuntu7 => 1:5.0.1-0ubuntu8~23.10.1)
3 upgraded, 0 newly installed, 0 to remove and 5 not upgraded.
Need to get 1804 kB of archives.
...

root@c2:~# grep LXC_DEVEL /usr/include/lxc/version.h
#define LXC_DEVEL 0