I just tried to redeem a code for a Mac app through iTunes.
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Apple identify that I’m using the code in the wrong place and tell me what to do (use the Mac App Store), but they could easily do better.
Better: Instead of a red error message – why not give me a link that opens the Mac App Store with the code pre-filled?
According to Stack Overflow, this link used to work:
macappstores://buy.itunes.apple.com/WebObjects/MZFinance.woa/wa/redeemLandingPage?code=NHWEL3FHRYKR
As of April 23rd 2019, that link opens the right page – but doesn’t pre-fill the code. (I have filed a bug)
Best: Why not just redeem the code for me? I’m already logged in on my mac with the right account.