Hello Vasily,

I followed the steps you suggested and was unable to reproduce the behavior you're describing.

I created a sample of XamGrid and set the TextWrapping property to wrap the header text.
In the sample I also set the ColumnWidth to "SizeToCells" and now when I run the sample and resize or shrinking the column my column header text is still wrapping ,it’s not trim.

I have attached the sample project I used to test this. Please test this project on your PC; whether or not it works correctly may help indicate the nature of this problem.
If the project does not work correctly, this indicates either a problem possibly specific to your environment, or a difference in the DLL versions we are using. My test was performed using version 17.2.20172.2029.

If the project does show the product feature working correctly, this indicates a possible problem in the code of your application. It will help if you can provide a small, isolated sample application that demonstrates the behavior you are seeing.
Or, if this sample project is not an accurate demonstration of what you're trying to do, please feel free to modify it and send it back, or send a small sample project of your own if you have one.

, myHello