What made you use throwaway email for this op? as I only use such for accounts I never cared much or willing to throwaway. If you're worried about exposing your email address, perhaps an email alias service could be of some use to you.
theymos advised that if user didn't use an actual email for account registration, a throw away or non existing email for registration, that user can change it to an email address with the forum domain. It's safer.
Make sure that your email address is secure. If you don't want to set an email address, use something like yourUserName@invalid.bitcointalk.org; don't use a random nonsense email like y@x.com, since somebody might create that domain/email.
Perhaps you might be interested on password managers like keepass.info? this made things so much more convenient for me as I only need to remember one password to access hundres of my accounts lol. Plus your keepass database is stored locally and is encrypted. Passwords are also better off randomized though computer generated would be better than humans which fortunately, keepass also offers.
[Guide] How to create and use a strong password?Keepass is available for Android too.
https://keepass.info/https://keepassxc.org/download/#windowshttps://play.google.com/store/apps/details?hl=en&id=com.android.keepasshttps://pwsafe.org/https://proton.me/passAvoid LastPass because they have
security incident.