I am using SSRS 2016 and Report Builder. I need the page breakinging with a group to be conditional on the value of a parameter. Does anyone know if this is even possible?
Another workaround, which seems to work quite nicely - place a parent group of the group you want to selectively break on, then in Group Properties for that, group on a derived expression of either the group field, or a fixed value. And then tick the box for that grouping as per your screenshot.
e.g. Assuming a parameter called "BreakPages", and a grouping on a field called "MyGroupField", you group on:
=iif(Parameters!BreakPages.Value="Y", Fields!MyGroupField.Value, "None")
You don't need to display any fields in this special group, it'll simply use the page break setting as per your requirements..