Today I was trying to change my Master Password and my Secret Key for my 1Password.eu Family account in the Web App. First, I let the 1P regenerate the Secret Key. Then I tried to also change the MP afterwards, but everytime I tried that, 1P told me that the current MP was wrong. Which definitely was not the case.
After I had logged out and back in, I could change the MP without a problem.
I was using Firefox 57 on Windows 10
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