I created the attached latex.org based on the example with pgf/tikz and it exports fine into a pdf. But export to html causes the problem, that I get only a link to the created graph. If I change :file to :file fsa.png, an image is included but it is a) very small and b) nearly completely black.
I guess, it has to do with the size of the png - but how can I change it? :width and :height do not seem to have any impact.
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