Possible null reference argument for parameter 'source' in 'IEnumerable<List<T>> Enumerable.Where<List<T>>(IEnumerable<List<T>> source, Func<List<T>, bool> predicate)'.

Dereference of a possibly null reference.

Possible null reference argument for parameter 'item' in 'void List<IIndexedPeak>.Add(IIndexedPeak item)'.

Nullable value type may be null.

The annotation for nullable reference types should only be used in code within a '#nullable' annotations context.

The annotation for nullable reference types should only be used in code within a '#nullable' annotations context.

Cannot convert null literal to non-nullable reference type.

Cannot convert null literal to non-nullable reference type.

The annotation for nullable reference types should only be used in code within a '#nullable' annotations context.

Cannot convert null literal to non-nullable reference type.

Possible null reference argument for parameter 'source' in 'IEnumerable<List<T>> Enumerable.Where<List<T>>(IEnumerable<List<T>> source, Func<List<T>, bool> predicate)'.

Dereference of a possibly null reference.

Possible null reference argument for parameter 'item' in 'void List<IIndexedPeak>.Add(IIndexedPeak item)'.

Nullable value type may be null.

The annotation for nullable reference types should only be used in code within a '#nullable' annotations context.

Cannot convert null literal to non-nullable reference type.

Cannot convert null literal to non-nullable reference type.

The annotation for nullable reference types should only be used in code within a '#nullable' annotations context.

The annotation for nullable reference types should only be used in code within a '#nullable' annotations context.

Cannot convert null literal to non-nullable reference type.