Ubuntu Version:
- Distributor ID: Ubuntu
- Description: Ubuntu 18.04.1 LTS
- Release: 18.04
- Codename: bionic
The package manager will not install packages from the extension SDK section.
The issue is that from version 17 onwards (so since April 13, 2017), the version of libpng supported is libpng16-16, not libpng12-0.
Can this please be fixed in the package manager?
$ sudo apt-get install libpng12-0
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package libpng12-0 is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
E: Package 'libpng12-0' has no installation candidate
Please see this screenshot: 