Microsoft Released A New Experimental Razor Editor For Visual Studio

You can try the new editor with the latest Preview 4 of VS 2019 16.7

Microsoft released the new experimental Razor editor for local development with MVC, Razor Pages, and Blazor. You can try the new editor with the latest Preview 4 of Visual Studio 2019 16.7
To enable the new experimental Razor editor in VS 2019 16.7 Preview 4 or later you will need to go to Tools > Options > Environment > Preview Features. There you can select the Enable experimental Razor editor option. Then, select OK and restart Visual Studio.
Source: Microsoft
Razor is an HTML and C#-based templating language which is used to define dynamic rendering logic for .NET web apps based on MVC, Razor Pages, and Blazor.
Microsoft said that to enable broader support for Razor editing, the company has worked on new Razor editor for ASP.NET Core projects based on a Razor Language Server. This new Razor Language Server uses the Language Server Protocol (LSP), which specifies a standard way for an editor or IDE to enable editor features such as auto-completion, go to description, etc . Then, an IDE-specific Razor extension manages communication with the Razor Language Server and other HTML & C # language servers.
Source: Microsoft
All Razor editor features have not yet been fully implemented and will be added in a future release. These include JavaScript and CSS IntelliSense support; Colorization for C#, JavaScript, CSS, Blazor components, Tag Helpers, and tooltips; URL picker support in HTML; C# snippets (‘prop’, ‘ctor’, etc.); and more.
For additional details, you can visit the official announcement here.