Electrum PSBT QR incompatible code

[massimopavoni]

It seems like it is not possible to sign PSBTs created on a watch-only Electrum wallet through scanning with Vault.

Trying to scan any generated QR code from Electrum (manually generated QR code after copying to clipboard the TX, or directly shown inside the application, though that one is stripped from information because of too big transactions) leads to the error:

Incompatible code

Could not parse code.
Please make sure this is a valid AirGap code.
You can try to handle this code in AirGap Wallet by using the "Relay" button below.

What is a valid AirGap code? As far as I know the partially signed transactions from Electrum hold all the information needed for them.
I do know that Electrum does not implement multiple QR code signing (I mention this because after failing to read the QR code, the Vault scanner changes to This transaction consists of multiple QR codes. [...]

I don't know if installing the AirGap Wallet on my offline device would fix that, but I'd rather not have to do that, if it was the case.

[mlaeng]

We never tested AirGap Vault to run with Electrum and installing AirGap Wallet on the offline device would not resolve your issues with Electrum.

But what you could do is to install AirGap Wallet on an online mobile phone and then use it with the Vault on the offline device.