if Salah follows him to leave can Liverpool replace the duo with other players? I think it's really difficult to do as much as Liverpool can keep one of them, because Liverpool really rose because of the cohesiveness of their striker to become the best in the EPL.
It's hard to imagine if Salah and Mane left.
Letting Mane and Salah leaves is a loss for Liverpool, their lifespan is not too old. They are still capable of playing for a long time. If they want a raise the salary is natural. They have played well and have contributed to the achievements of the club. If they leave Klop will certainly have a hard time finding a replacement. Right now they are in ideal team conditions they only need to correct a few mistakes in the season. Maybe buying a few players will add to them getting stronger.
Of course it's a big loss that they have both been able to play a number of seasons with contributing displays and that's a lethal striker this season, clearly needs to be kept up and the pay rise is due to his performances.
This is actually just a rumor, hopefully there is a good chance for them to stay there, but indeed the competition in the transfer market is tight with the lure of big money, players will be tempted if there is a bigger offer, because in football money can change everything.