Great question. No. I used "receive" tab, it gave me the address. I didn't even have addresses tab turned on in my view. I was new to Electrum. The second time I was using "receive" tab it gave me another address and I remember I was googling, if it was normal for Electrum to have different recieveing addresses.
When you request a receive address, Electrum will choose the next available one that has no transaction history yet AND is not already listed in the "Requests" section on the Receive tab.
When a requested receive address has been funded, it's totally normal and desired behavior that Electrum (or any other decent Bitcoin wallet) chooses a new unused receive address when asked for it.
I've found an article on the forum that I was reading, when I was creating a wallet. Thats a huge leap forward.
It was stated there, that second index in derivation path for Bitcoin is 44 (m/44'/0'/0'/0/0), and for Ethereum is 60 (m/44'/60'/0'/0/0).
I believed it was a common knowledge and changed it to 44, I'm pretty sure.
That still doesn't give me my wallet adress, I guess I changed smth in other indexes too. But much less to bruteforce now.
You may want to give
https://github.com/bitcoin/bips/blob/master/bip-0044.mediawiki a read.
We define the following 5 levels in BIP32 path:
m / purpose' / coin_type' / account' / change / address_index
Apostrophe in the path indicates that BIP32 hardened derivation is used.
Each level has a special meaning, described in the chapters below.
...
If you get to the address type and derivation path choice dialog during restore, you MUST have used the BIP39 mnemonic recovery words option in Electrum.
Purpose
44' or
44h basically refers to BIP44 and legacy address derivation for Bitcoin (coin_type
0' or
0h.
You could still have chosen native Segwit address type and a derivation path of
m/44h/0h/0h instead of the default value of
m/84h/0h/0h on the account level as Electrum expects it at this step. It doesn't matter if you use
m/44h/0h/0h or
m/44'/0'/0', both are equivalent.
m/44'/0'/0'/0/0 is full path derivation up to the individual address' path, here first receive Bitcoin address of first account of a HD wallet according to BIP44. On account level (
m/44'/0'/0') it's not recommended to use any unhardened index/path.
Change index (receive addresses is index 0, change addresses is index 1) and address_index are typically non-hardened paths.
Whatever you've chosen for the derivation path, basically regardless of its length, Electrum would've accepted it as long as the indices are in the valid range. (I haven't tested if there's some derivation path length limit in Electrum.)
As a warning...
My idea was to make a wallet, that noone can access even knowing all my passwords and having a physical access to all my belongings.
You were quite successful with that, likely not as intended by you, because "noone" includes yourself!
If you had kept at least one backup Electrum wallet file, it would've been possible to look up the used derivation path at menu Wallet>Information. Sadly, you deleted them all without any backup or copy in Recycle bin. Apple has Time Machine or iCloud sync. None of that used? (Well, cloud sync could be dangerous if you have poor wallet encryption passphrases. Don't forget: a cloud is someone else's computers.)