Copy part of Notes?

Ok ok! I think I know what's going on. Today I experienced an issue with copy and paste not registering and I tried my best to reproduce it and successfully did.

Basically what happened is Marriott was forcing its users to change their passwords, so I went ahead and did that. To do that I do the following:

1. Hit Edit in 1Password app
2. Click on password field, click on "Create new password"
3. Generate a new password and click Use
4. Now I have my new password. I don't save this because I'm not 100% sure new password will be accepted, so I switch back to browser, fill in the change password form which requires current password, and proposed password. Current password is already autofilled because I did that before changing password
5. I CMD+A + CMD+C on the password field to copy the new password to fill into my Marriott page, and then to my surprise sometimes the clipboard is either my old password or whatever was previously in my clipboard.

Problem is I can't reproduce this 100% of the time, but a lot of times it seems that copying the password field in its edit state doesn't fully store it in the clipboard. The only thing I can see that may affect how this happens is how fast I CMD+TAB out to my next window. I think there may be a delay in the CMD+C or something because I do see the Edit menu flash, and then I CMD+TAB over, but if I wait a solid second or two, the clipboard never fails. Only when I CMD+TAB over quickly, it seems to fail. I don't think I'm doing it too quickly because I routinely copy paste all the time (website to Excel, Excel to text editor, Keynote to email, Messages to Notes, etc.).