just privete key or seed?
if seed - that is problem. Electrum has 13 words seed al other use 12 words seed.
Electrum seed has only 12 words. Are you sure you did not write one more by mistake? Try to recheck your seed by going to "Wallet" -> "Seed".
THX alote. That is clever. But
1) If I move all BTC from old Electrum wallet to somewhere else
2) by using seed or private-key will open my public key in any SBTC wallet
3) will step 1 fluence on getting SBTC or not? The screenshot was done 12.12.17. At that time I used to have BTC on my electrum wallet... Is that enought?
If the fork already happened, it doesn't matter if you move your Bitcoins or not. The forked coins will stay there.
Why electrum as supporter on SBTC web page if u are singe cripto wallet. ?)
No idea. Probably to give them a fake legitimacy. Electrum will probably never support a differentt Bitcoin (especially these shitcoins).