After installing gnome-shell, the font size of my program appears small

I installed gnome-shell to get rid of the top bar
But there is a problem.
I am running my program automatically at boot time, but after installing gnome-shell, the font size of my program appears small.
(The program was made with qtcreator)
If you close the program and run it again, the font size returns to its original size.
The font size is small only when autostart is started after booting.
I need to autostart after booting my program.
How do I get the font size to return to its original size even after autostart? Help me.

Hi,
This would need other users to share experience. For running application at startup, we have several cases listed in Jetson Nano FAQ
Q: How to autorun an app or commands at startup?

What we have tried is to put the command in ~/.xsessionrc Not sure if this is applicable in your use-case and can avoid the issue.

This isn’t a Jetson issue so much as it is a Qt issue. You might be able to just use Qt environment variables. Try this on command line, then run your app; if it works, put it in your startup environment:

QT_ACCESSIBILITY=1
QT_SCALE_FACTOR=1.5
QT_AUTO_SCREEN_SCALE_FACTOR=1

(you can experiment with those to find the right combination)