Nullability of type of parameter 'obj' doesn't match overridden member (possibly because of nullability attributes).

Cannot convert null literal to non-nullable reference type.

Converting null literal or possible null value to non-nullable type.

Dereference of a possibly null reference.

Converting null literal or possible null value to non-nullable type.

Converting null literal or possible null value to non-nullable type.

Possible null reference argument for parameter 'fileName' in 'CascFoundFile.CascFoundFile(string fileName, nint plainName, byte[] encodingKey, CascLocales locales, long fileSize, CascStorageContext ownerContext)'.

Non-nullable field 'filename' must contain a non-null value when exiting constructor. Consider declaring the field as nullable.

Non-nullable field 'prevname' must contain a non-null value when exiting constructor. Consider declaring the field as nullable.