Wechat cookie and localstorage fail
this is the case:
Wechat opens page a, and when page an enters, it determines whether userid exists. If not, use cookie or localstorage to store a random userid with a hyperlink in page a, like this
.
this code will be called after clicking the hyperlink and going to the page benerary b to submit a form.
window.open("","_self");
window.close();