Fix structural formulas on Wikipedia (#621)
Fix structural formulas on Wikipedia (#621)

The structural formulas of chemicals on Wikipedia are often rendered on a transparent background, making them illegible. For example:
https://en.wikipedia.org/wiki/Polyethylene
darkreader/darkreader,alexanderby/darkreader,alexanderby/darkreader,darkreader/darkreader,alexanderby/darkreader,darkreader/darkreader