Recently, to take advantage of testnet incentives and earn some points, the group has started guessing whether the mainnet will issue tokens... The more these times, the easier it is to get carried away and click on links randomly. Think of mnemonic phrases like bank card passwords; any "synchronize/verify/import" pages asking you to fill in should be closed immediately, don't take chances. Don't blindly confirm signature authorizations either; if you don't understand, refuse first, better to do fewer tasks. If you really need to do them, try to split addresses and funds, only receive in the main wallet and avoid touching it. To put it simply, airdrops are not guaranteed yet, so first keep the safety red line intact, or else while doing side tasks, you might end up losing the main line.