Apple's web browser & more, Safari, highest versions there are for
Leopard and Leopard Server. Official files/format issued by Apple.
The last zip download for 5.0.6 is Apple's initial 20110707 build-file
posted to their web site 20110720 (but here without its dmg wrapper).
The previous dmg download for 5.0.6 is one they built/reissued in
2012. All older versions here are the initial releases.
