Following R's lead (https://www.r-bloggers.com/2018/06/its-easy-to-cite-and-reference-r/), I think we should also have a citing proposition, e.g. somewhere in the about dialog. For example:
"To cite LabPlot in publications use:
LabPlot Team (2022), LabPlot: A FREE, open source, cross-platform Data Visualization and Analysis software accessible to everyone, (Version 2 10) [Computer software]. https://labplot.kde.org.
We have invested a lot of time and effort in creating LabPlot, please cite it when using it for data analysis or visualization."