Hi wills,
Thanks for contacting Syncfusion support,
Based on your query you have an issue with column chooser which is placed inside the Dialog component. So, we have prepared a sample with your code example but we did not reproduce the mentioned issue at our end.
We have shared the sample for your reference.
Please refer the below screenshot and sample for more information.
Screenshot:
1) Please share your Syncfusion package version.
2) Share your complete Grid rendering code.
3) If possible please replicate the problem with our above attached sample.
4) If possible share the pictorial representation or video demonstration of the issue.
Let us know if you have any concerns.
regards,
Praveenkumar