The Scorch browser plugin is now incompatible with all major browsers on all computer platforms, because all major browsers are going to 64-bit.
There is now no browser, 32-bit or 64-bit, that can run the Scorch plugin on the Mac platform.
ScoreExchange just announced that they are trying to find a way not to use Sibelius Scorch to sell sheet music anymore, and so is every other business that relies on Sibelius Scorch to sell or distribute sheet music.
Avid must re-write the Scorch browser plug-in to modern standards. There has been no significant updates to the Scorch plugin in six years or more..