So I'm really trying not to be aggressive about this situation but... The whole system of your all passwords are being secured by another password (which Opera decides it and literally mentions it about anywhere but the options section only) is so trash Imma lose my mind. The way to put your saved passwords in secure (as all the other browsers do) should be putting them Inside Your Account, like any other important data being kept.
So my problem is: I was putting all my password in this Opera system (knowing that I'm trusting it too much) and then just reseted my PC for various reasons. And after the reset I downloaded Opera and suddenly got this error: "You should enter your synchronization master passphrase to get your synced passwords". And do you know what's the funniest part? It says "if you forgot it (or never knew there was such thing) you can basicly erase all of the password data of yours which only we have acces! :)" I know there is another option that says "if you enter your old password of your account, you can acces to it." But it doesn't working for me and I don't know why.
Normally for these kinda situations companies has a help center and if you can prove that the data you're looking for is yours, you can get them. Unfortunetly Opera doesn't have that either. Writing all of these here for a hope of getting usefull help and to remind you all reliability of good old writing down your passwords on paper.

@leocg As I remember I changed my account password twice. And I found the previous one.
So I'm guessing when it says "old password" it means the very first one not the previous.

@leocg And I'm just gonna pretend like you didn't say that. Because hell I don't even know how many website accounts I had stored in Opera. I have litterally tons of accounts. If what you say was the correct way, either you had to make your all passwords same and like "yourname123" or you had to be 200IQ or somethin. And why do you writing them down if you can store them all in your brain in the first place?

@leocg Yeah the thing is, as I mentioned above, I'm entering my old account password and it does not accepts it. And I have never set a passphrase myself.

So I'm really trying not to be aggressive about this situation but... The whole system of your all passwords are being secured by another password (which Opera decides it and literally mentions it about anywhere but the options section only) is so trash Imma lose my mind. The way to put your saved passwords in secure (as all the other browsers do) should be putting them Inside Your Account, like any other important data being kept.
So my problem is: I was putting all my password in this Opera system (knowing that I'm trusting it too much) and then just reseted my PC for various reasons. And after the reset I downloaded Opera and suddenly got this error: "You should enter your synchronization master passphrase to get your synced passwords". And do you know what's the funniest part? It says "if you forgot it (or never knew there was such thing) you can basicly erase all of the password data of yours which only we have acces! :)" I know there is another option that says "if you enter your old password of your account, you can acces to it." But it doesn't working for me and I don't know why.
Normally for these kinda situations companies has a help center and if you can prove that the data you're looking for is yours, you can get them. Unfortunetly Opera doesn't have that either. Writing all of these here for a hope of getting usefull help and to remind you all reliability of good old writing down your passwords on paper.