H5ad converts string/object to categorical when saving and reading

[wangjiawen2013]

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Hi, My anndata.obs has a column of dtype object(string), but when I saved the h5ad and read again with scanpy, the column became categorical ! Then it made conflicts with my spatialdata objects.

adata.write("adata.h5ad")
sc.read_h5ad("adata.h5ad")

Versions

the anndata version: 0.10.8
the scanpy version: 1.10.2

[wangjiawen2013]

[flying-sheep]

Duplicate of #534, which has been fixed on main: in the next AnnData release, you can set convert_strings_to_categoricals=False