@hobbyProgrammer said in window closes after completing certain actions.: @JonB Hi, just a quick update. I think it does get there, but it prints this part before going executing the slot. It's really important for those who try to help you to give accurate description of what does/does not happen. Everyone was trying to figure how your connect() could not complete and get to the next line....

@JonB oh that was really stupid. I was meant to check another QVector of QPolygons...