Thank you for clarifying, this property isn't available for UI for Xamarin Cross Platform (Xamarin Forms), which is the product you submitted a ticket for.
If you're using Xamarin.iOS and UI for iOS (via Xamarin wrappers), then you should be able to set the header's height by using the Style property (as seen in that documentation link you pointed to):
.sideDrawer = TKSideDrawer.FindSideDrawer(0,
sideDrawer.Style.HeaderHeight = 50;
sideDrawer.Style.FooterHeight = 50;
sideDrawer.Style.ItemHeight = 30;
If this doesn't work for you, please share your TKSideDrawer implementation with us so that we can replicate your issue and debug it directly.
Lance | Tech Support Engineer, Sr.
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