SUMMARY
LabPlot2 crashes when I attempt to duplicate a "box plot" in an existing Worksheet in version 2.9.0 27ef7ef. This occurs if I use the "Duplicate Here" option or the copy and paste options, and there is no "crash detected" window.

It should be noted that I am using the Flatpak nightly build, and unfortunately I haven't figured out how to get debug traces out of it. (I'm not that familiar with Flatpak nor gdb, although if the bug is proving hard to reproduce I could attempt to set up an environment for compiling KDE directly.) 

STEPS TO REPRODUCE
1. Create a spreadsheet with some arbitrary data. I used two columns of about seven data points, but it also occurs with one column.
2. Create a box plot in a new worksheet/plot using the Create Plot tool.
3. Right click on the "Box Plot" that is newly created and select "Duplicate Here." The program should crash to desktop.


OBSERVED RESULT
LabPlot2 crashes instantly with no visible error dialogs.

EXPECTED RESULT
The box plot would be duplicated, allowing me to (for example) color code two sets of data and two box plots differently within the same document. 

SOFTWARE/OS VERSIONS
Linux/KDE Plasma:  Arch Linux x86_64. KDE Flatpak runtime

KDE Plasma Version: KDE Flatpak runtime, system Plasma is 5.23.5
KDE Frameworks Version: 5.90.0
Qt Version: 5.15.3 

ADDITIONAL INFORMATION
Development version installed using the instructions here: https://labplot.kde.org/download/