write anndata failed, pearson_residuals_df header message is too large

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Minimal code sample (that we can copy&paste without having any data)

Write any anndata with pearson residuals in uns

ad_all.write(filename='output/10x_h5/ad_all_2cello.h5ad')

The pearson_residual_df looks like this, with 38291 rows (obs) and 5000 columns (features) :

{'theta': 100,
 'clip': None,
 'computed_on': 'adata.X',
 'pearson_residuals_df': gene_name                             A2M  AADACL2-AS1      AAK1     ABCA1  \
 barcode                                                                      
 GAACGTTCACACCGAC-1-placenta_81  -1.125285    -1.159130 -3.921314 -2.533474   
 TATACCTGTTAGCTAC-1-placenta_81  -1.091364     3.267127 -1.806667 -2.109586   
 CTCAAGAGTGACTGTT-1-placenta_81  -1.074943    12.272920 -1.948798 -2.735791   
 TTCATTGTCACGAACT-1-placenta_81  -1.098699    -1.131765  3.481171  4.472371   
 TATCAGGCAGCTCATA-1-placenta_81  -1.107734    -1.141064 -0.571775 -2.813671   
 ...                                   ...          ...       ...       ...   
 CACAACATCGGCGATC-1-placenta_314 -0.115585    -0.119107 -0.434686 -0.303945   
 AGCCAGCGTGCCCAGT-1-placenta_314 -0.097424    -0.100394 -0.366482 -0.256219   
 CCGGTGAGTGTTCGAT-1-placenta_314 -0.110334    -0.113696 -0.414971 -0.290148   
 AGGTCATAGCCTGACC-1-placenta_314 -0.115585    -0.119107 -0.434686 -0.303945   
 TTTATGCCAAAGGGTC-1-placenta_314 -0.112876    -0.116316 -0.424515 -0.296827 

Unable to create attribute (object header message is too large)

Above error raised while writing key 'pearson_residuals_df' of <class 'h5py._hl.group.Group'> to /

Versions

Start with the ad_all.write(filename='output/10x_h5/ad_all_2cello.h5ad') example and trace how the uns key pearson_residuals_df is written through the h5py Group. Reproduce the object-header error with the supplied dimensions and versions; done means writing an AnnData object containing pearson_residuals_df succeeds without the reported error.