Can I use JSONata to access elements of a msg.payload when it's a buffer of byte?

[Steve-Mcl]

@cymplecy

But I've never managed to understand how to use it

It's not so bad once you "get it". And once you do, you realise why it's laid out as it is and it's power.

You can of course read the explanations in the built in help but this example should give you a head start: