The up and down arrows are not disabled when selecting the first or the last member in Images Collection Editor

[Amy-Li03]

• .NET Core Version: 5.0.100-preview.5.20227.13

• Have you experienced this same bug with .NET Framework?: Yes

Problem description: The up and down arrows are not disabled when selecting the first or the last member.

Expected behavior: The up arrow should be disabled when selecting the first member. The down arrow should be disabled when selecting the last member.

More info:

1. This issue also can reproduce with .Net Core 3.1.
2. This issue also can reproduce for MonthCalndar/ListView/TabControl/treeView controls.

Minimal repro:

1. Create a winforms core project.
2. Add a propertyGrid and a ImageList controls to form designer.
3. Add this code in the construction method of form: propertyGrid1.SelectedObject = imageList1;
4. Run the core project.
5. Find the Images property of ImageList, click the Browser button to show the Images Collection Editor.
6. Click the Add button to add 4 images in it, then select the last member.
7. Observe the down arrows on the right of the images.

Or

1. Run the attached project. TestApp.zip
2. Do the above step 5-7.

[merriemcgaw]

This is not actually a no-op in code.