---

This section details on the original issue you should resolve

<issue_title>IDE0048 triggers for is null but not for is not null in null-coalescing expressions</issue_title>
<issue_description>Version Used:
Visual Studio 2026 v18.0.0
.NET 10

Steps to Reproduce:

1. Create a class like the following:

internal sealed class Test
{
    public override bool Equals(object? obj)
    {
        return Equals(obj as Test);
    }

    public override int GetHashCode()
    {
        return 0;
    }

    public static bool operator ==(Test? left, Test? right) => left?.Equals(right) ?? right is null; // <- Triggers IDE0048

    public static bool operator !=(Test? left, Test? right) => !left?.Equals(right) ?? right is not null; // <- Does not trigger IDE0048
}

2. Observe that left?.Equals(right) ?? right is null; triggers IDE0048, while !left?.Equals(right) ?? right is not null; does not.

Diagnostic Id:
IDE0048 Parentheses should be added for clarity

Expected Behavior:
IDE0048 should behave consistently, it should either trigger for both cases or for neither. For reference, Rider considers parentheses redundant in both cases.

Actual Behavior:
IDE0048 is triggered for the is null check but not for the is not null check.</issue_description>

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