Firefox 45.0.1 was one of the last versions to support older operating systems that have since been phased out by modern web standards. Minimum Requirement Windows XP SP2, Vista, 7, 8, or 10 Mac Mac OS X 10.6 through 10.11 Linux GTK+ 2.18, GLib 2.22, Pango 1.14 Hardware Pentium 4 or newer (SSE2 support required) The Extended Support Release (ESR) Factor
Released just eight days after the major 45.0 update, version 45.0.1 was primarily a designed to address regressions that appeared in the initial launch. mozilla firefox 450 1 old version
To maintain enterprise compatibility, non-standard jar: URIs were brought back to fix a regression affecting IBM iNotes . Firefox 45