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Describe the bug

I have a Blazor WASM page that renders a table with 16 columns of data over 4 types of objects. Each of these 4 objects only renders some of the columns and the rest are colspan together. I have between 400 to over 100K records. I implemented Virtualize and it works perfectly even with the 100K rows.

Now, I have a single button, outside of the Virtualize area but still within the containing scroller div that displays a modal. The modal code is outside of even the containing scroller. If the modal container is set to display: none the checkboxes I have within the Virtualize are quite slow (1 second for only about 400 rows) and up to 30 seconds when I have the 100K rows.

Another implementation I tried where there was a razor if statement surrounding the modal code, when the modal was not showing, the checkboxes worked great. Once the modal is displayed, the checkbox list I have in the modal (where there are 126 choices) is very laggy, for some reason relative to how many rows are in the Virtualize data (which has nothing to do with the modal.)

I have more detail in my stack overflow post.

In the most recent update, I added it seems to have nothing to do with the modal (I thought it may have some sort of interaction issue with the virtualize and the modal on top) but that is not the problem because I put the select list below the virtualize grid.

Expected Behavior

I would like the modals to work, no matter how many components exist in it or anywhere on the page.

Steps To Reproduce

I created this from scratch (14 of the columns just really had text or expand collapse capabilities) and these all worked. Once I added the two columns that had a single checkbox in each, the Virtualize still worked. Then I moved on to the modal and that is where the lagging came in. Turns out, it does not even need to be a modal.

Exceptions (if any)

No response

.NET Version

6.0.101

Anything else?

.NET SDK (reflecting any global.json):
Version: 6.0.101
Commit: ef49f6213a

Runtime Environment:
OS Name: Windows
OS Version: 10.0.19043
OS Platform: Windows
RID: win10-x64
Base Path: C:\Program Files\dotnet\sdk\6.0.101\

Host (useful for support):
Version: 6.0.1
Commit: 3a25a7f1cc

.NET SDKs installed:
5.0.401 [C:\Program Files\dotnet\sdk]
6.0.101 [C:\Program Files\dotnet\sdk]

.NET runtimes installed:
Microsoft.AspNetCore.App 3.1.19 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 5.0.10 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 6.0.1 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.NETCore.App 3.1.19 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 5.0.10 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 6.0.1 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.WindowsDesktop.App 3.1.19 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 5.0.10 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 6.0.1 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]