Documentation should not redirect to .NET 4.8 documentation if it doesn't apply to .Net 3+ Winforms.

[MelonWang1]

Describe the issue or suggestion

See the WinForms issue dotnet/winforms#8866

Issue description
Users evaluating .NET 6/7 will search the internet and find documentation on learn.microsoft.com (but for .NET 4.8)
They use the combobox to select .NET 6/7 and are redirected back to the 4.8 documentation.
When it is wrong, they assume nothing has changed and the documentation is relevant for them.
They don't go to the Github repro and check the wiki/docs there that are more correct.
They get confused and call Microsoft.

example, customer wondering why his controls wouldn't show up in the Winform's designer toolbox even though he was following the documentation.
here are a few links in that area.
learn.microsoft.com/en-us/dotnet/desktop/winforms/controls/how-to-display-a-control-in-the-choose-toolbox-items-dialog-box?view=netframeworkdesktop-4.8&viewFallbackFrom=netdesktop-6.0

https://learn.microsoft.com/en-us/dotnet/desktop/winforms/controls/walkthrough-automatically-populating-the-toolbox-with-custom-components?view=netframeworkdesktop-4.8&viewFallbackFrom=netdesktop-6.0

https://learn.microsoft.com/en-us/dotnet/desktop/winforms/controls/how-to-display-a-control-in-the-choose-toolbox-items-dialog-box?view=netframeworkdesktop-4.8&viewFallbackFrom=netdesktop-6.0

Steps to reproduce

1. Navigate to learn.microsoft.com/en-us/dotnet/desktop/winforms/controls/how-to-display-a-control-in-the-choose-toolbox-items-dialog-box?view=netframeworkdesktop-4.8
2. Change the combobox from .NET Famework 4.8 to .NET 7

Actual Results
Still looking at the 4.8 docs even though things don't work that way anymore, but thinking they still apply.
We need correct documentation.

Diagnostics：
There is a banner at the top that states...
"The requested page is not available for .NET 6.0. You have been redirected to the newest product version this page is available for."
However, every customer and support engineer I have talked to miss it. I think it looks too much like an Ad, and we've been trained to ignore content that doesn't look like it's part of the article, but that is just a guess.

[adegeo]

@MelonWang1 This isn't the correct repo for desktop issues. I'll move this issue

[adegeo]

That banner at the top isn't controllable, it's the same across the whole site I believe. The reason there is a redirect is because that page doesn't exist for the non-framework docset. We need to create an article for it.

[Prologh]

I've been just hit with this one, so annoying. Can't see if a class is available in older .NET versions because of this redirect thing.

https://learn.microsoft.com/en-us/dotnet/api/microsoft.extensions.caching.memory.imemorycache?view=net-9.0-pp&viewFallbackFrom=net-8.0