But like Alipay do they suddenly block your non-Mainland card for "security reasons" until you provide copies of the card, your passport, and a recent card statement?

And something else I've learned with Alipay. If you can't link your Mainland bank card for any of a number of reasons, you can still pay for things with your Mainland bank card through online banking, if you have a PC handy with IE installed. Saves the Alipay 3 percent credit card fee, plus your bank's foreign-use credit card fee.

(I see I can now bring up a QR payment code on the Alipay app with just a non-Mainland credit card linked, but don't know whether it works for payment.)

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