eclipse window builder work abnormaly in zorin os

I am using zorin os 16 pro. I am using eclipse in windows machine for few months. It works fine in windows. But problem in zorin os. I download eclipse from [this](https://flathub.org/apps/details/org.eclipse.Java) site. All things are fine except window builder. The drag & drop, border is not correct. Like this image I have installed WindowBuilder 1.9.8 and WindowBuilder Nightly Build 1.9.9. Is there any solution out there? Need help. I have googled but not find the solution yet. Anyways, I love eclipse because I can customize all the code generated. Is there any alternative like eclipse? So that I can customize all codes include auto generated code? I have tried netbeans and intellij but I can not customize generated code. Sorry for my bad english. Thanks to all. I have tried saveral ways like change layout, drag and drop etc.