With the current implementation using the preview package there is a problem when using multi-line text. The result file is not cropped by the content bounding box anymore but by the full page width. This results in huge text labels in LabPlot.

Alternatively, the package "standalone" could be used which also support cropping and has an option "varwidth" which should help here:

https://texblog.org/2012/09/12/cropping-the-output-file-to-its-content-in-latex/

Consider using this package instead of preview. standalone doesn't seem to be part of the default installation of TexLive, though...