Thank you yes .


That only applies to exported fully signed raw transactions.
Even the file export (.txn) shows the same hex characters when opened as text.

If unsigned, Electrum will export it in PSBT format, via save to clipboard (base64) or file export (.psbt)


Ah yes you are correct it only works on the signed tx. Thanks.



Cold-storage Electrum setup supports QR Code export and scan,
That essentially fulfills your main goal to eliminate the usage of flash drive in your setup

Yeah I'm confused why I get a warning that qr code can not contain all the data of the psbt unsigned tx.
When I scan it on the airgapped machine it gives a warning yellow triangle says cant put the fees and it can be maliciously changed.

When I transfer on usb it works fine and no warning.

Is there any particularly reasonable explanation why you must use Bitcoin Core in your Air-Gap machine instead of another offline Electrum?

Well only that I was wondering if I could avoid doing a dumprivkey to core to put that into electrum. The wallet.dat was made in core and even a key logger could only see my passphrase to sign at the moment and I think if it could slip out a passphrase hopefully it could not slip out a wallet.dat

I'm able to scan qr code for signed as it seems all the info can easily fit inside.

So I can use the airgapped electrum but at the moment I still have to bring the unsigned psbt with usb so I guess there is some danger something slips in to the airgapped machine. 

I probably shouldn't use that usb again even though I do format it straight away as soon as I used the psbt from it 

Someone suggested to me you can break the unsigned data into parts and make several qr codes but I got lost on his idea.

Thanks for pmalek also for warning about possible issues in the future.