Hello, how to make it safe? When I'm trying to change e-mail I can easily change it without any notification via e-mail. Pls any advices?
You can use
different password for each site, so if one account gets hacked, not all ur accounts are obtained.
Also use strong password with capital letter, numbers and special signs, so your account won't be easily cracked. And do not fall for scams/phising sites or download malicious software.
I don't think bitcointalk.org will change a thing about changing the email so easily.
This do not use one password for lot's of sites if you do, one hack/leak and they will test many sites with your email/username and password that was "hacked". I firmly believe is a mix of password manager and physical token in Yubikey.
This makes it where you cannot access my password manager without a password, and a physical token so cant be remotely activated via software. I have to press a button on my yubikey.
Also prepare for worse case scenario by staking an address. So if ever needed you can recover your account on bitcointalk.