Caused by 6a79a6a24a
`Mask` `AnimData` is read by `BKE_animdata_blend_read_data` since above
commit, so `BLO_read_data_address` on `AnimData` is already done there.
However, `mask_blend_read_data` does it again
Similar calls to `BLO_read_data_address` in `blend_read_data` callbacks
were usually removed in 6a79a6a24a, Masks being an exception.
Accoding to @mont29 the reason while a double remapping will fail is
because there can only be one remapping from old addresses to new ones.
Once the new address has been read, this new address cannot be used as
'key' again (it will likely map to nothing, or worse, remap to something
completely unrelated!)
Pull Request: https://projects.blender.org/blender/blender/pulls/119961
7da9521c7c