I turned a GUI that I wrote in python into an executable via
chmod +x mygui.py, added a shebang. Then I added this script to the "Session and Startup" list of programs (Settings -> Session and Startup) in order to run it when I turn on my computer. When I reboot my computer, the GUI is opened but some of its widgets are not drawn.
Edit: After opening the properties of a launcher I created on my desktop for the same python script, I realized that the difference is that the launcher has a "working directory" which the startup manager doesn't know about. I am pretty sure that this is the reason why some widgets aren't loading since they use some icons and other elements that are in the same directory as the script. So now my question is, how do I tell ubuntu where to look for everything in my script when it opens it on startup? Thank you.