On Wednesday 21 October 2020, Stephen John Smoogen smooge@gmail.com wrote:
[yves@home firefox]$ ./firefox ./firefox: /lib64/libc.so.6: version `GLIBC_2.17' not found (required by ./firefox) ./firefox: /lib64/libc.so.6: version `GLIBC_2.14' not found (required by ./firefox)
CentOS 6 only goes up to glibc 2.12.
Basically that says that upstream no longer thinks that Firefox is runnable on RHEL-6/CentOS-6 anymore.
That message was from Firefox 78.4 ESR downloaded from Mozilla. Obviously Red Hat does think that it's possible to run Firefox 78.3 ESR on RHEL 6, because they shipped it. They just didn't get the sound working properly.
But end of life is in 6 weeks, so perhaps nobody will bother fixing the problem.