That's because the application build with higher glibc then running. Someone choose to manually upgrade glibc, but because of the importance of glibc in GNU/Linux, this method usually make the whole OS distroyed. There's some safer but more complex solution, however, the utility here is much easier using and installing, without troubles to damage your operating system.
There's no license restriction with scripts such as ablrun. All the library files are taken from some GNU/Linux distribution, their original license should followed.
2. It use bwrap, as a result, some application may not run, such as ones use there own container or ones need to mount filesystem. But appimages will run, because I designed a special method to support.
3. Also include a single libstdc++ library with glibc, because this problem is as often as that with glibc.
4. You may use LD_LIBRARY_PATH environment variable with ablrun to search libraries in other directories, which may solve some other library problem.
If the released package cannot fit your needs (such as library version, architecture), you may try make-deb.sh to create your own additional base lib. Download the project, and edit the script, change 3 URLs for download packages to which you want. You may found many version and architectures from debian page: https://www.debian.org/distrib/packages , and then run the script make-deb.sh. It will auto-detect achitecture of packages, and take corresponding methods.
