Merge pull request #803 from timunie/patch-1

Update README with DataGrid styles instructions

Author: luke-whos-here

docs/reference/controls/datagrid/README.md

@@ -48,7 +48,7 @@ Note you must always install the data grid version that matches the _Avalonia UI
 
 You must reference the `DataGrid` themes to include the additional styles that the `DataGrid` uses. You can do this by adding a `<StyleInclude>` element to the application (`App.axaml` file).
 
-For example:
+For example (In case you use `FluentTheme`):
 
 ```xml
 <Application.Styles>
@@ -57,6 +57,11 @@ For example:
 </Application.Styles>
 ```
 
+:::warning
+The DataGrid-styles need to match the overall theme you use, otherwise you will get conflicts and unresolved resources. For third party themes, please lookup their docs and samples.
+:::
+
+
 ## Useful Properties
 
 You will probably use these properties most often: