Code Inspection: Join or separate attributes is section
Multiple attributes in C# can be written in different ways: you can join several attributes in the same square brackets section or use several sections for different attributes. ReSharper allows you to specify the style for multiple attributes and enforce this style in the desired scope.
By default, multiple attributes are checked for compliance with your preferences and if they do not comply, JetBrains Rider highlights such declarations and suggests the corresponding quick-fix or fix in scope.
For more information about configuring and enforcing your preferences for multiple attributes, see Code Syntax Style: Multiple Attributes.