Thank you for your using the UI for Blazor forums. However, there isn't enough information to fully understand the question. Let me explain more below.
Generally, the header row is not required to lock for vertical scrolling within the grid as shown in the Grid - Freeze Columns demo. This is because only the content of the grid is vertically scrollable. For more details on column locking, see the Grid Frozen Columns article.
Additionally, there is a feature named "row pinning" which is not available in Blazor. To see this in action, refer to the React Grid - Locked Rows demo. This enables locking a certain row within view. Although, I am not certain this is what you're looking for.
If the built-in header row locking isn't suitable for your scenario, i.e. for page scrolling and not just scrolling within the grid, it may be possible to make the header row frozen during page scroll by applying CSS to the HTML header element. See the following code snippet for how to do this.
Note that the exact configuration depends on the scenario and the position of the other elements on the page and will require some adjustments.
If the above information and potential workaround doesn't meet your needs, I will need to understand the scenario better. In this case, I ask that you provide more information on the requirement and the Grid markup and code-behind for review.
In the meantime, please let me know if you need any additional information. Thank you.
Eric R | Senior Technical Support Engineer
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