[HDPI] SystemAware controls inside containers anchored with Bottom or Right are messed up.

[kirsan31]

.NET version

.Net9

Did it work in .NET Framework?

Not tested/verified, but I think - NO.

Did it work in any of the earlier releases of .NET Core or .NET 5+?

Not working with .Net8, and I think with oldest too.

Issue description

Form designed and launched with 125% dpi:

If AnchorStyles.Bottom is used then problems are more huge:

This is one of more others issues with anchoring Bottom / Right and HDPI:
#5076
#8157
#10958
#11516
...

Setting:

{
  "configProperties": {
    "System.Windows.Forms.AnchorLayoutV2": true
  }
}

in runtimeconfig.template.json will solve the issues.

Steps to reproduce

TabControlAnchorBug.zip

[Zheng-Li01]

@kirsan31 using the below configurations can make the controls inside containers scaled well.

{
  "configProperties": {
    "System.Windows.Forms.AnchorLayoutV2": true
  }
}

14034.mp4

[kirsan31]

@Zheng-Li01 wow thanks. You are right AnchorLayoutV2 resolve this issues.
I completely missed everything related to AnchorLayoutV2 and it's clear why - there no any mentions about it in what's new for .Net8 🤷‍♂️ Google (except AI) also find almost nothing. And only after searching this repo I found the article: https://github.com/dotnet/winforms/blob/main/docs/design/anchor-layout-changes-in-net80.md

[paul1956]

@Zheng-Li01 the instructions need more context, I believe I need to add a new file runtimeconfig.template.json in the same directory as my project file (if it does not exist) and then add or merge the JSON content above.

As @kirsan31 said this was very difficult to discover.

[Balkoth]

Using WinForms for ages and never heard of this switch...