delete HowMany() extension method and just use .Count() instead, the one value add of null/empty checking was never utilized anyway

src/BizHawk.Client.Common/tools/Watch/WatchList/WatchList.cs

@@ -400,7 +400,7 @@ namespace BizHawk.Client.Common
 					continue;
 				}
 
-				var numColumns = line.HowMany('\t');
+				var numColumns = line.Count(c => c == '\t');
 				int startIndex;
 				if (numColumns == 5)
 				{

src/BizHawk.Common/Extensions/NumericStringExtensions.cs

@@ -27,7 +27,7 @@ namespace BizHawk.Common.StringExtensions
 		/// This method returning <see langword="true"/> for some <paramref name="str"/> does not imply that <see cref="float.TryParse(string,out float)">float.TryParse</see> will also return <see langword="true"/>.<br/>
 		/// Also this has nothing to do with fixed- vs. floating-point numbers, a better name would be <c>IsUnsignedDecimal</c>.
 		/// </remarks>
-		public static bool IsFixedPoint(this string? str) => !string.IsNullOrWhiteSpace(str) && str.HowMany('.') <= 1 && str.All(IsFixedPoint);
+		public static bool IsFixedPoint(this string? str) => !string.IsNullOrWhiteSpace(str) && str.Count(c => c == '.') <= 1 && str.All(IsFixedPoint);
 
 		/// <returns><see langword="true"/> iff <paramref name="c"/> is <c>'-'</c>, <c>'.'</c>, or a digit</returns>
 		/// <remarks>Also this has nothing to do with fixed- vs. floating-point numbers, a better name would be <c>IsSignedDecimal</c>.</remarks>
@@ -80,7 +80,7 @@ namespace BizHawk.Common.StringExtensions
 		/// This method returning <see langword="true"/> for some <paramref name="str"/> does not imply that <see cref="float.TryParse(string,out float)">float.TryParse</see> will also return <see langword="true"/>.<br/>
 		/// Also this has nothing to do with fixed- vs. floating-point numbers, a better name would be <c>IsSignedDecimal</c>.
 		/// </remarks>
-		public static bool IsFloat(this string? str) => !string.IsNullOrWhiteSpace(str) && str.HowMany('.') <= 1 && str[0].IsFloat() && str.Substring(1).All(IsFixedPoint);
+		public static bool IsFloat(this string? str) => !string.IsNullOrWhiteSpace(str) && str.Count(c => c == '.') <= 1 && str[0].IsFloat() && str.Substring(1).All(IsFixedPoint);
 
 		/// <returns>
 		/// <see langword="true"/> iff <paramref name="str"/> is not <see langword="null"/>,

src/BizHawk.Common/Extensions/StringExtensions.cs

@@ -5,9 +5,6 @@ namespace BizHawk.Common.StringExtensions
 {
 	public static class StringExtensions
 	{
-		/// <returns>how many times <paramref name="c"/> appears in <paramref name="str"/>, or <c>0</c> if <paramref name="str"/> is null</returns>
-		public static int HowMany(this string? str, char c) => string.IsNullOrEmpty(str) ? 0 : str.Count(t => t == c);
-
 		/// <returns><see langword="true"/> if <paramref name="str"/> appears in <paramref name="options"/> (case-insensitive)</returns>
 		public static bool In(this string str, params string[] options) => options.Any(opt => string.Equals(opt, str, StringComparison.InvariantCultureIgnoreCase));
 	}