Mozilla is basing their Linux builds of the ESR 78 series on Debian
Jessie and we switched recently to that, too. However, given the EOL
situation of Jessie we should investigate moving to something newer,
e.g. Debian Stretch.
To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information
It seems RHEL/CentOS 7 is using glibc 2.17. Debian Stretch is using glibc 2.24, so if we switch to that maybe it won't work on RHEL/CentOS 7. Although I don't know if we have many RHEL/CentOS 7 users.