No it is exactly one version ahead, the number is just bigger by 13. Firefox ESR 102 is based on firefox non-esr 102 and ESR 115 is based on non-ESR 115. There

No it is exactly one version ahead, the number is just bigger by 13. Firefox ESR 102 is based on firefox non-esr 102 and ESR 115 is based on non-ESR 115. There are no ESR versions in between. As an analogy think of fedora and red hat https://en.wikipedia.org/wiki/Red_Hat_Enterprise_Linux#Relationship_with_Fedora_Linux https://en.wikipedia.org/wiki/Red_Hat_Enterprise_Linux#Relat... With that same scheme it would be red hat 6, 12, 19, 28, 34 instead of 5,6,7,8,9.