In an UWP application when I set TargetPlatformVersion and TargetPlatformMinVersion to 10.0.17763.0, 10.0.18362.0 or 10.0.19041.0 (I keep them always aligned) I found that pages are not released from memory causing serious issues, as the application memory usage quickly grows up.
This GitHub repo contains the code that reproduce the problem https://github.com/DanieleScipioni/MemoryLeak, this a basic application with 2 pages. You can just go from the first page to the second, the second page contains a ListView of ListViews with an ItemClick event handler.
<Page x:Class="MemoryLeak.Views.ListsPage">
<Grid>
<ListView IsItemClickEnabled="True"
CanReorderItems="False"
ItemsSource="{x:Bind _secondPageViewModel.List, Mode=OneWay}">
<ListView.ItemsPanel>
<ItemsPanelTemplate>
<ItemsStackPanel Orientation="Horizontal" />
</ItemsPanelTemplate>
</ListView.ItemsPanel>
<ListView.ItemTemplate>
<DataTemplate x:DataType="local:StringList">
<ListView ItemsSource="{x:Bind}"
ItemClick="ListView_OnItemClick"
IsItemClickEnabled="True"/>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</Grid>
</Page>
To see the memory leak is enough to go forward and back from the 2 pages, and see memory increasing on the Task Managed, anyway I used Visual Studio Diagnostic Tool.
With Visual Studio Diagnostic Tool I execute this test: open app, go to next page, go back and take a snapshot, again go to next page, go back and take a another snapshot, then stop data collection and compare the 2 snapshots. GC is started several time before of each snapshot.
With TargetPlatformVersion 10.0.19041.0, there are 205 more objects in the second snapshot

and looking at count diff and at paths to root I see this

So at the end ListsPage is not released from memory.
The behavior must be that both count and count diff is 0, meaning that ListsPage is released from memory.