Created attachment 124489 [details]
The file that was effected.

1. Open this labplot file.
2. There are 2 plots in it but with no lines.
3. Select 5% CO2 plot, then hover over the selected plot.
4. Use mouse scroll to change to plot scale randomly.
5. Disable and re-enable the Auto x-range and Auto y-range scaling under General.
6. The lines for both graph should appear.
7. Save the file, close it, then open the same file again.
8. The line is now gone because the scale or position change itself.

labplot-kf5-2.7.0-1.3

Operating System: openSUSE Tumbleweed 20191207
KDE Plasma Version: 5.17.3
KDE Frameworks Version: 5.64.0
Qt Version: 5.13.1
Kernel Version: 5.3.12-1-default
OS Type: 64-bit
Processors: 8 × Intel® Core™ i7-3770 CPU @ 3.40GHz
Memory: 7.5 GiB of RAM