Comment 21 for bug 1525418

@Maren - if I force a local installation of Inkscape 0.91 (90dpi) to be the one spawned by script extensions of Inkscape 0.92.1 (96dpi), I can reproduce your result from comment #14 (but only then). In my understanding, this is more a "side-effect" of working with several custom installations of Inkscape alongside a stable official package, without properly vetting all aspects of that (rather than a bug in one specific extension script).

I would recommend to carefully adjust $PATH in any launcher scripts you might use for local inkscape builds installed into a custom prefix; e.g. to prepend the 'bin' folder of the custom prefix to $PATH.