What version of Electrum did you use to create the wallet?
I used electrum in tails when i created the wallet. I am not sure which version, because shortly after i created the wallet tails updated to 2.10 and i think electrum got updated too. I can post which version of electrum tails currently uses later.
Do you still have the wallet file for this wallet?
I used the save a copy of this wallet function but if try to open it now it shows me an error about splitting files up, and electrum version incompatibility, which is why i think tails changed the version of electrum with their 2.10 update.
You may be able to try looking at the wallet configuration files and see if you are able to recover the private keys for this wallet based on the information in the files.
Can i do this even when the "opening" process as descriped above isn't working?
You do have a 12 word seed that was used for this wallet but creating a new wallet with this seed generates a different wallet?
Exactly, but i have a 13 word seed if that changes something. Apperently the same word seed generates 2 different wallets depending on wether they are used as standard wallet or hardware wallet seeds.