[Bug] CollectionView with itemtemplate selector and bindable layout behaves strangely on iOS

[StevenGranados]

Description

I have a CollectionView where you can add either a simple int or a List of objects with ItemTemplate set to a selector. I have a bindable StackLayout with a selector in one of the templates on the CollectionView. On adding items the CollectionView behaves strangely, refreshes and places new items in the middle of the list. Only broken in iOS, android fine.

Steps to Reproduce

1. Open repro.
2. Click AddModel and Add SImple alternately until page full.
3. Scroll to bottom.
4. CollectionView refreshes on adding items.

Expected Behavior

CollectionView adds items to bottom of list.

Actual Behavior

CollectionView refreshes and adds items to middle temporarily, and starts overlapping items.

Basic Information

• Version with issue :4.3.0.851321-pre3
• Last known good version: In 4.2 just freezes once screen is full or all the items disappear.
• IDE: Visual Studio 2019 16.3.2
• Platform Target Frameworks:
  • iOS: 13.0
• Affected Devices: iPhone 8 simulator

Screenshots

Reproduction Link

CollectionViewTemplateSelectors.zip

[PureWeen]

Probably a duplicate of this one
#7714