Thank you for your response.
I can't find the "Replace by fee" option, instead I have a box "Edit fees manually" ; I suppose I should check it ?
If you want, but its not what I was looking for. Sounds good as it should give you more control.
Just below, there is another option : "Propose replace-by-fee", associated with a scrolling menu : "If the fee is low / Always / Never"...should I choose the first one ?
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They change it a bit around, so setting it to 'Always' should do it.
Can you help me understand how it works : can the "network" determine if a fee is low, and then I would have a message suggesting to increase it ?
No, but your wallet can or rather the server its connected to. It knows about most other unconfirmed transactions and can estimate which will get confirmed (soon) and which not (or later).
Also, another question, in the "Receive" menu (I wish to bring my BTC back from my Bitstamp account), Electrum provides the address that I need for asking Bistamp to send me the BTC, which is clear. But there is also an empty box for the requested amount. If I write 1 in this box, and then 1 in the Bitstamp "deposit" formular, will the fees be taken from my Bitstamp account (sender) or from my Electrum BTCs. A true beginners' question...Thank you for your assistance.
No, this just changes the information that is encoded in the QR code. See how it changes when you enter an amount? It handy to set a label for someone elses wallet or similar, but it has no meaning if you just copy the address.