In Magento 2 the option to allow customer to change how many products to show per page is a default feature.
Can we save the option customer chose so that when the customer goes to another category they see as many products per page as they chose to earlier in the first category?
Looks like since at least 2.3.1, there's a setting in Stores > Configuration > Catalog > Catalog > Storefront: Remember Category Pagination to enable this feature. 
Yes. Create a session variable and save the chosen value. Use this to get the number of product base on the session variable value.
