Render LaTeX is not working in Inkscape after installing to 18.04

Assuming you use Latex Inkscape plugin, texText, it support pdf2svg beside ghostscript+pstoedit. So, in case of Ubuntu 18.04, installing pdf2svg solves the problem

sudo apt install pdf2svg

It works for me on Ubuntu 18.04, InkScape 0.92.

In this specific case building pstoedit from source does not solve the problem because the svg backend is not included by default (as already experienced above). Hence, I propose to update ghostscript to version 9.23.

After downloading and extracting the ghostscript source tarball from https://www.ghostscript.com/download/gsdnld.html enter the source directory and execute the following three commands:

./configure --prefix=/usr
make
sudo make install

This simply overwrites the existing ghostscript version and then one does not need to fiddle around with dependencies.

If you encounter problems elsewhere due to the new gs version you can easily switch back by

sudo apt-get install ghostscript --reinstall

Drawback of this solution is that security updates of ghostscript installed by the system will overwrite your installation and you need to re-install. However, as long as there are no pre-built binaries available this might be a first workaround