Do updates to the Designer still ship in VS2026?

[robertmclaws]

I have a code generation framework that is not .tt based and relies on the EDMX specification. That framework is the most productive when you can use the EDMX designer to push and pull changes to and from the database.

I have an EDMX in an SDK-based project that has .NET Framework 4.8 specified first, then .NET 9.0.

It will not open in the solution. But:

• When the provider is set to System.Data.SqlClient, it will open by itself when I right-click and select "Visual Studio Version Selector" to open it with.
• When the provider is set to Microsoft.Data.SqlClient and you do the above it will not open at all.

I'm going to use Claude Code to fix the designer so that:

• it will open in .NET 8+ projects
• it will work with the Microsoft.Data.SqlClient provider
• it will output the entity diagram as an SVG

The question is, if I submit a PR here will it make it into Visual Studio, or will I need to ship my own extension?

[ErikEJ]

@robertmclaws Would be interesting to see the amount of changes required. Might also help answering your question.

[robertmclaws]

Thanks @ErikEJ! I just opened a draft PR that I'm still contributing to. All tests (including all my new ones) are currently passing, and I can finally open EDMX files on my machine again.

Claude almost one-shotted the SVG feature but I'm currently iterating on it now. Should be finished in the next few hours.

One thing I should note is that Claude added a fair amount of logging in a few spots to help us isolate and fix the problem. I can take that logging out if you'd like but so far it's been pretty useful.

[robertmclaws]

I will also point out that there are a number of things I had to do to my machine to get this version working instead of the OOB one. I had to rename the .pkgdef file and the Bootstrap assembly in the existing installed extension, and also run the following PowerShell script to overwrite files that get installed into Common7\IDE.

# Self-elevate if not running as Administrator
if (-not ([Security.Principal.WindowsPrincipal][Security.Principal.WindowsIdentity]::GetCurrent()).IsInRole([Security.Principal.WindowsBuiltInRole]::Administrator)) {
    Start-Process powershell.exe "-ExecutionPolicy Bypass -File `"$PSCommandPath`"" -Verb RunAs
    exit
}

$source = "$env:LOCALAPPDATA\Microsoft\VisualStudio\18.0_93d9f2a2Exp\Extensions\Microsoft Corp\Microsoft Data Entity Design Package\1.0"
$dest = "C:\Program Files\Microsoft Visual Studio\18\Insiders\Common7\IDE"

Write-Host "Copying DLLs from extension to VS install directory..."

Copy-Item "$source\Microsoft.Data.Entity.Design.VersioningFacade.dll" "$dest\Microsoft.Data.Entity.Design.VersioningFacade.dll" -Force
Write-Host "  VersioningFacade.dll"

Copy-Item "$source\Microsoft.Data.Entity.Design.Model.dll" "$dest\Microsoft.Data.Entity.Design.Model.dll" -Force
Write-Host "  Model.dll"

Copy-Item "$source\Microsoft.Data.Entity.Design.dll" "$dest\Microsoft.Data.Entity.Design.dll" -Force
Write-Host "  Design.dll"

Copy-Item "$source\Microsoft.Data.Entity.Design.EntityDesigner.dll" "$dest\Microsoft.Data.Entity.Design.EntityDesigner.dll" -Force
Write-Host "  EntityDesigner.dll"

Copy-Item "$source\Microsoft.Data.Entity.Design.Package.dll" "$dest\Microsoft.Data.Entity.Design.Package.dll" -Force
Write-Host "  Package.dll"

Copy-Item "$source\Microsoft.VisualStudio.Data.Tools.Design.XmlCore.dll" "$dest\Microsoft.VisualStudio.Data.Tools.Design.XmlCore.dll" -Force
Write-Host "  XmlCore.dll"

Write-Host "`nDone. Restart VS to use the updated DLLs."
Read-Host "Press Enter to close"

It was really weird that assemblies were also getting loaded there. Perhaps at some point they should be removed so the EFDesigner package can be fully self-contained? (I know none of this may seem relevant in 2026, but the EF designer still produces the most visually-appealing entity diagrams out there)

[ErikEJ]

Maybe you should spilt your PR into bug fixes and new features?

Makes it simpler to review and maybe increases the chances of the fixes actually being accepted.

[robertmclaws]

I've added a code review guide to help understand how the PR is broken down, with a bunch of stats and links. My initial viewpoint was that I may only get one shot at updates, so I wanted whoever reviews it to see the changes I wanted to make in context with everything else.

If after reviewing it, you'd still like me to break everything out, I can see about having Claude Code separate out the changes.

In a perfect world, I'd love the opportunity to upgrade the solutions to .slnx files, the projects to SDK-style, see if there are ways to get the design surface to load faster, and add some more output options to the Export system.

Thanks so much for your help and consideration!

[dbreshears]

@robertmclaws . I apologize for not seeing this earlier.

The latest version of EF6Tools are still supported in Visual Studio 2026, however the EF6Tools are no longer being actively developed. This means that:

• Security issues will be fixed, as for any supported product.
• High-impact bugs, typically those impacting a very large number of users, may be fixed.
• Other bugs will not be fixed.
• New features will not be implemented

[robertmclaws]

What is the point in continuing to ship this in Visual Studio if it throws exceptions when you attempt to open EDMX files in modern projects?

I don't feel like it would have hurt anything to least have a discussion about whether or not it makes sense to ship an update in the age of Claude Code.

No matter. I'm more than happy to fork it and ship a replacement myself. 🤷‍♂️

[ErikEJ]

@dbreshears It would be helpful if these conditions were mentioned in the readme