If people send you some bitcoins but use a low fee It can stay unconfirmed for a long time.  You dont actually have those coins yet.

If you want to continue to spend and use your fully confirmed funds without mingling in these unconfirmed funds is the best way to ensure there is a tick next to the option ^ spend only confirmed coins ?

Will making sure that has a tick next to it

A/ stop you spending any of your coins until these coins sent to you with low fees confirm fully

Or

B/ electrum will ignore those low fee unconfirmed coins and just spend from your confirmed coins?

I am wondering why it is unticked by default? I see someone sending me some bitcoin with 5 sats fees.
That will likely not get confirmed for a long time so I dont want that to mess up my confirmed funds.


So if I put a tick next to the spend only confirmed what will happen A or B.

I assumed B but seeing the tick is not there by default made me doubt and I cannot find the exact answer.

Thanks.