problems with svg images

Bug Description

I'm trying to export .svg files of my molecules and they're rendering incorrectly in most viewers, including Firefox and PowerPoint. Claude said something about Cairo using feImage or a compositing filter technique.

My Ubuntu Image Viewer can render the file and so I can zoom in and take a screenshot if I need images for a slideshow, but it's not the same. The vectorized image can be resized while a .png starts to introduce losses.

I was able to generate .svg files a year ago, and I'm nervous that if things break down further, I won't be even able to get high quality screenshots.

Example Code

import rmgpy.species
sp = rmgpy.species.Species(smiles='O=CCO[O]')
sp.molecule[0].draw('example.svg')

Start by reproducing the example with rmgpy.species and molecule.draw('example.svg'). Inspect how the SVG is generated, then compare the output in Firefox and PowerPoint with Ubuntu Image Viewer, as reported. Done means the exported SVG renders correctly in the affected viewers while remaining a scalable vector image.