Extension class to use rich text in Unity Console. https://docs.unity3d.com/Manual/StyledText.html

StringTagExt.cs

public static class StringTagExt
{
	public static string AddBoldTag(this string text)
	{
		return text.AddTag("b");
	}

	public static string AddItalicTag(this string text)
	{
		return text.AddTag("i");
	}

	public static string AddSizeTag(this string text, int size)
	{
		return text.AddTag("size", size);
	}

	public static string AddColorTag(this string text, string colorName)
	{
		return text.AddTag("color", colorName);
	}

	private static string AddTag(this string text, string tagName)
	{
		return $"<{tagName}>{text}</{tagName}>";
	}

	private static string AddTag(this string text, string tagName, object value1)
	{
		return $"<{tagName}=\"{value1}\">{text}</{tagName}>";
	}
}