A few days ago I decided to switch from Bitcoin Core to Electrum, as running a full node when firewalled by a NAT is quite ridiculous.

As far as I understand, an entity knowing a wallet's master public key can identify all used Bitcoin addresses (e.g. all the addresses with a transaction history) of this specific wallet on the blockchain (plus all addresses that will ever be used in the future), but can't spent any funds.

So my question is: Does Electrum communicate the master public key to the server it is connected to? In that case a malicious server operator could severely compromise the privacy of Electrum users...

Btw: In case I got something completely wrong; please enlighten me!