Staking Etheruem could lose your Ethereum?

I was thinking about staking all my ethereum on coinbase when I saw this in the terms and agreements, see below. I didnt know I could lose my ethereum I stake. So they want us to stake our ethereum to get a chance at getting 6% apr, with the possibility of losing all of my ethereum?

Is this a possibility if I stake somewhere else also?

(c) No Guarantee of Success of Network Upgrade. Coinbase makes no guarantees that the upgrade to the Ethereum network will be successful, and you understand that if the network upgrade ultimately fails, you may lose all, or a portion of, your staked ETH. Coinbase will not be responsible for any ETH lost due to a network upgrade failure.