diff --git a/core/modules/filters.js b/core/modules/filters.js
index aa82a352a..054a5d493 100644
--- a/core/modules/filters.js
+++ b/core/modules/filters.js
@@ -200,12 +200,20 @@ exports.parseFilter = function(filterString) {
 
 exports.getFilterOperators = function() {
 	if(!this.filterOperators) {
-		$tw.Wiki.prototype.filterOperators = {};
-		$tw.modules.applyMethods("filteroperator",this.filterOperators);
+		$tw.Wiki.prototype.oldFilterOperators = {};
+		$tw.modules.applyMethods("filteroperator",this.oldFilterOperators);
+		$tw.Wiki.prototype.newFilterOperators = {};
+		$tw.modules.applyMethods("newfilteroperator",this.newFilterOperators);
+		$tw.Wiki.prototype.filterOperators = $tw.utils.extend({},$tw.Wiki.prototype.oldFilterOperators,$tw.Wiki.prototype.newFilterOperators);
 	}
 	return this.filterOperators;
 };
 
+exports.isFilterOperatorNew = function(name) {
+	this.getFilterOperators();
+	return name in $tw.Wiki.prototype.newFilterOperators;
+};
+
 exports.getFilterRunPrefixes = function() {
 	if(!this.filterRunPrefixes) {
 		$tw.Wiki.prototype.filterRunPrefixes = {};
@@ -214,11 +222,21 @@ exports.getFilterRunPrefixes = function() {
 	return this.filterRunPrefixes;
 }
 
-exports.filterTiddlers = function(filterString,widget,source) {
+exports.filterTiddlersPolymorphic = function(filterString,widget,source) {
 	var fn = this.compileFilter(filterString);
 	return fn.call(this,source,widget);
 };
 
+exports.filterTiddlers = function(filterString,widget,source) {
+	var results = this.filterTiddlersPolymorphic(filterString,widget,source);
+	for(var t=0; t<results.length; t++) {
+		if(typeof results[t] !== "string") {
+			results[t] = $tw.utils.filterItemToString(results[t]);
+		}
+	}
+	return results;
+};
+
 /*
 Compile a filter into a function with the signature fn(source,widget) where:
 source: an iterator function for the source tiddlers, called source(iterator), where iterator is called as iterator(tiddler,title)
@@ -255,16 +273,19 @@ exports.compileFilter = function(filterString) {
 				currTiddlerTitle = widget && widget.getVariable("currentTiddler");
 			$tw.utils.each(operation.operators,function(operator) {
 				var operands = [],
-					operatorFunction;
+					operatorFunction,
+					operatorName;
 				if(!operator.operator) {
 					// Use the "title" operator if no operator is specified
 					operatorFunction = filterOperators.title;
+					operatorName = "title";
 				} else if(!filterOperators[operator.operator]) {
 					// Unknown operators treated as "[unknown]" - at run time we can distinguish between a custom operator and falling back to the default "field" operator
 					operatorFunction = filterOperators["[unknown]"];
 				} else {
 					// Use the operator function
 					operatorFunction = filterOperators[operator.operator];
+					operatorName = operator.operator;
 				}
 				$tw.utils.each(operator.operands,function(operand) {
 					if(operand.indirect) {
@@ -277,7 +298,17 @@ exports.compileFilter = function(filterString) {
 					}
 					operands.push(operand.value);
 				});
-
+				// If this is a legacy monomorphic operator then wrap the accumulator source in a wrapper that converts each item to a string
+				if(!self.isFilterOperatorNew(operatorName)) {
+					var innerAccumulator = accumulator;
+					accumulator = function(iterator) {
+						innerAccumulator(function(ignored,item) {
+							var title = $tw.utils.filterItemToString(item),
+								tiddler = self.getTiddler(title);
+							iterator(tiddler,title);
+						});
+					};
+				}
 				// Invoke the appropriate filteroperator module
 				results = operatorFunction(accumulator,{
 							operator: operator.operator,
diff --git a/core/modules/filters/count.js b/core/modules/filters/count.js
index 638b135df..5b9d5af41 100644
--- a/core/modules/filters/count.js
+++ b/core/modules/filters/count.js
@@ -1,7 +1,7 @@
 /*\
 title: $:/core/modules/filters/count.js
 type: application/javascript
-module-type: filteroperator
+module-type: newfilteroperator
 
 Filter operator returning the number of entries in the current list.
 
@@ -20,7 +20,7 @@ exports.count = function(source,operator,options) {
 	source(function(tiddler,title) {
 		count++;
 	});
-	return [count + ""];
+	return [count];
 };
 
 })();
diff --git a/core/modules/filters/json-ops.js b/core/modules/filters/json-ops.js
index 0c58964eb..8413038bb 100644
--- a/core/modules/filters/json-ops.js
+++ b/core/modules/filters/json-ops.js
@@ -1,7 +1,7 @@
 /*\
 title: $:/core/modules/filters/json-ops.js
 type: application/javascript
-module-type: filteroperator
+module-type: newfilteroperator
 
 Filter operators for JSON operations
 
@@ -57,9 +57,9 @@ exports["jsonindexes"] = function(source,operator,options) {
 exports["jsontype"] = function(source,operator,options) {
 	var results = [];
 	source(function(tiddler,title) {
-		var data = $tw.utils.parseJSONSafe(title,title);
-		if(data) {
-			var item = getDataItemType(data,operator.operands);
+		var data = $tw.utils.filterItemToObject(title,{defaultValue: title,parseStringsAsJson: true});
+		if(data !== undefined) {
+			var item = getFilterItemType(data,operator.operands);
 			if(item !== undefined) {
 				results.push(item);
 			}
@@ -196,7 +196,7 @@ function convertDataItemKeysToStrings(item) {
 	return [];
 }
 
-function getDataItemType(data,indexes) {
+function getFilterItemType(data,indexes) {
 	// Get the item
 	var item = getDataItem(data,indexes);
 	// Return the item type
@@ -281,4 +281,3 @@ function setDataItem(data,indexes,value) {
 }
 
 })();
-	
\ No newline at end of file
diff --git a/core/modules/filters/math.js b/core/modules/filters/math.js
index 6b1d45f08..30209e938 100644
--- a/core/modules/filters/math.js
+++ b/core/modules/filters/math.js
@@ -1,7 +1,7 @@
 /*\
 title: $:/core/modules/filters/math.js
 type: application/javascript
-module-type: filteroperator
+module-type: newfilteroperator
 
 Filter operators for math. Unary/binary operators work on each item in turn, and return a new item list.
 
@@ -207,7 +207,7 @@ function makeNumericBinaryOperator(fnCalc) {
 		var result = [],
 			numOperand = $tw.utils.parseNumber(operator.operand);
 		source(function(tiddler,title) {
-			result.push($tw.utils.stringifyNumber(fnCalc($tw.utils.parseNumber(title),numOperand)));
+			result.push(fnCalc($tw.utils.parseNumber(title),numOperand));
 		});
 		return result;
 	};
@@ -226,7 +226,7 @@ function makeNumericReducingOperator(fnCalc,initialValue,fnFinal) {
 		if(fnFinal) {
 			value = fnFinal(value,result.length,result);
 		}
-		return [$tw.utils.stringifyNumber(value)];
+		return [value];
 	};
 };
 
@@ -238,7 +238,7 @@ function makeNumericArrayOperator(fnCalc) {
 		});
 		results = fnCalc(results);
 		$tw.utils.each(results,function(value,index) {
-			results[index] = $tw.utils.stringifyNumber(value);
+			results[index] = value;
 		});
 		return results;
 	};
diff --git a/core/modules/utils/simple-list.js b/core/modules/utils/simple-list.js
new file mode 100644
index 000000000..01ac68587
--- /dev/null
+++ b/core/modules/utils/simple-list.js
@@ -0,0 +1,86 @@
+/*\
+module-type: utils
+title: $:/core/modules/utils/simple-list.js
+type: application/javascript
+
+Switched from a linked list to simplify things
+
+\*/
+(function(){
+
+function SimpleList() {
+	this.clear();
+};
+
+Object.defineProperty(SimpleList.prototype,"length", {
+	get: function() {
+		return this.list.length;
+	}
+});
+
+SimpleList.prototype.clear = function() {
+	this.list = [];
+};
+
+SimpleList.prototype.remove = function(value) {
+	if($tw.utils.isArray(value)) {
+		for(var t=0; t<value.length; t++) {
+			this._remove(value[t]);
+		}
+	} else {
+		this._remove(value);
+	}
+};
+
+/*
+Push behaves like array.push and accepts multiple string arguments. But it also
+accepts a single array argument too, to be consistent with its other methods.
+*/
+SimpleList.prototype.push = function(/* values */) {
+	var values = arguments;
+	if(arguments.length === 1 && $tw.utils.isArray(values[0])) {
+		values = values[0];
+	}
+	for(var i = 0; i < values.length; i++) {
+		this._push(values[i]);
+	}
+	return this.list.length;
+};
+
+SimpleList.prototype.pushTop = function(value) {
+	// this.push(value);
+	// -or-
+	$tw.utils.pushTop(this.list,value);
+};
+
+SimpleList.prototype.each = function(callback) {
+	$tw.utils.each(this.list,callback);
+};
+
+SimpleList.prototype.toArray = function() {
+	return this.list.slice(0);
+};
+
+SimpleList.prototype.makeTiddlerIterator = function(wiki) {
+	var self = this;
+	return function(callback) {
+		self.each(function(title) {
+			callback(wiki.getTiddler(title),title);
+		});
+	};
+};
+
+SimpleList.prototype._remove = function(value) {
+	var p = this.list.indexOf(value);
+	if(p !== -1) {
+		this.list.splice(p,1);
+	}
+};
+
+SimpleList.prototype._push = function(value) {
+	this.list.push(value);
+};
+
+exports.SimpleList = SimpleList;
+
+})();
diff --git a/core/modules/utils/utils.js b/core/modules/utils/utils.js
index 234de0c75..aad2f199e 100644
--- a/core/modules/utils/utils.js
+++ b/core/modules/utils/utils.js
@@ -1039,4 +1039,52 @@ exports.makeCompareFunction = function(type,options) {
 	return (types[type] || types[options.defaultType] || types.number);
 };
 
+exports.filterItemToString = function(value) {
+	switch(typeof value) {
+		case "undefined":
+			return "undefined"
+		case "object":
+			return JSON.stringify(value);
+		case "boolean":
+			return value ? "true" : "false";
+		case "number":
+			return value.toString();
+		case "bigint":
+			return value.toString();
+		case "string":
+			return value;
+		case "symbol":
+			throw "Filter operators cannot return Symbols";
+		case "function":
+			throw "Filter operators cannot return Functions";
+	}
+};
+
+exports.filterItemToObject = function(value,options) {
+	options = options || {};
+	var defaultValue = options.defaultValue || {};
+	switch(typeof value) {
+		case "undefined":
+			return defaultValue;
+		case "object":
+			return value;
+		case "boolean":
+			return value;
+		case "number":
+			return value;
+		case "bigint":
+			return value;
+		case "string":
+			if(options.parseStringsAsJson) {
+				return $tw.utils.parseJSONSafe(value,defaultValue);
+			} else {
+				return value;
+			}
+		case "symbol":
+			throw "Filter operators cannot return Symbols";
+		case "function":
+			throw "Filter operators cannot return Functions";
+	}
+};
+
 })();
diff --git a/editions/test/tiddlers/tests/test-filters.js b/editions/test/tiddlers/tests/test-filters.js
index 5626db4f8..195f38a26 100644
--- a/editions/test/tiddlers/tests/test-filters.js
+++ b/editions/test/tiddlers/tests/test-filters.js
@@ -708,6 +708,10 @@ Tests the filtering mechanism.
 			expect(wiki.filterTiddlers("1 2 3 4 +[min[2]]").join(",")).toBe("1,2,2,2");
 		});
 	
+		it("should handle type conversions", function() {
+			expect(wiki.filterTiddlers("[[2]add[2]addprefix[donkey]]").join(",")).toBe("donkey4");
+		});
+	
 	/* listops filters */
 		
 		it("should handle the allafter operator", function() {