cell_ranger flavor of highly_variable_genes expects non-logarithmized data?

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I believe this may be a bug in documentation. It says that scanpy.pp.highly_variable_genes expects logarithmized data, except when flavor='seurat_v3'. However, after reading the reference Zheng17 for the cellRanger method (in particular, Supplementary Figure 5c), it appears that non-logarithmized data was used for calculating the dispersion. And examining the highly_variable_genes source code, I note that for method='seurat', the data is transformed back out of logspace using X=np.expm1(X) before computing dispersions, but this is not done when method='cell_ranger'.

My conclusion is that the documentation should be updated to reflect that when flavor='cell_ranger', non-logarithmized data is expected. But I would very much appreciate clarification on the issue, it has been a long-standing source of confusion in our lab. Thank you.

Start with the highly_variable_genes source code and its documentation, then compare the cellRanger behavior with the Zheng17 reference, especially Supplementary Figure 5c. Confirm whether non-logarithmized data is expected and update the documentation or clarify the implementation so the documented input matches the verified behavior.