How to connect ASP.NET Core site to Master and Slave at the same time using Pomelo EF Core Driver?

Question

I have a master and a slave replica MySQL server that I want to connect via my ASP.NET Core application. My connection string is like this:

server=master.domain.com, slave.domain.com;port=3306;user=user;password=mysosecretpassword;database=mydb

However, my SELECT queries are not hitting the slave server. (I have tested it with a poor man's check, changing data on the slave by hand and checking it out on my application. I only see the master data)

Am I doing something wrong? Can't find anything related to master slave connection using Pomelo drivers.