Shopify: [Part II] Email Confirmation Bypass in myshop.myshopify.com that Leads to Full Privilege Escalation

Summary In #791775, I submitted a bug at Sunday 5pm Canada time, it was triaged two hours later, and I got the temp fix message at around 3am the next day in Canada time. Truly awesome, the next day I retested after the first fix, and found that I Cannot receive the email confirmation in the email used to sign up Cannot integrate across stores/partner even they share the same email address after confirming them And the report was later resolved after I verified the fix. For some reason, I decided to test again to see what's something new that I can find. Then I found user can change their email prior to receiving the verification message on their original email. i.e. the same technique, I don't know what went wrong in my first retest, but Shopify security and engineering team again showed their professionalism, quickly resolving the second comments I left in ~3.5 hrs. And when I thought this is the end of story, I later received a comment asking me to open a new report about the second retest, and here I am writing this report. Thanks, Ron Impact...