The Syncfusion native Blazor components library offers 70+ UI and Data Viz web controls that are responsive and lightweight for building modern web apps.
.NET PDF framework is a high-performance and comprehensive library used to create, read, merge, split, secure, edit, view, and review PDF files in C#/VB.NET.
If you want to change the size of this line, you need to handle QueryCellInfo, and in the handler if e.ColIndex points to your frozen column, then set e.Style.Border.Right = new GridBorder(....); to have teh border you want to see.