use normalized urls instead of unction strings as key

lib/single-file/single-file-core.js

@@ -1013,7 +1013,7 @@ this.SingleFileCore = this.SingleFileCore || (() => {
 		static async processStylesheet(doc, stylesheetContent, cssRules, baseURI, options, batchRequest) {
 			let sheetContent = "", variablesInfo = { index: 0, cssText: "" };
 			const urlFunctions = DomUtil.getUrlFunctions(stylesheetContent);
-			const urlFunctionData = new Map();
+			const resourceInfos = new Map();
 			await Promise.all(urlFunctions.map(async urlFunction => {
 				const originalResourceURL = DomUtil.matchURL(urlFunction);
 				const resourceURL = DomUtil.normalizeURL(originalResourceURL);
@@ -1021,10 +1021,10 @@ this.SingleFileCore = this.SingleFileCore || (() => {
 					const { content, indexResource, duplicate } = await batchRequest.addURL(resourceURL);
 					const regExpUrlFunction = DomUtil.getRegExp(urlFunction);
 					if (duplicate && options.groupDuplicateImages) {
-						urlFunctionData.set(urlFunction, { regExpUrlFunction, dataURI: content, variableName: "var(" + SINGLE_FILE_VARIABLE_NAME_PREFIX + indexResource + ")" });
+						resourceInfos.set(resourceURL, { regExpUrlFunction, dataURI: content, variableName: "var(" + SINGLE_FILE_VARIABLE_NAME_PREFIX + indexResource + ")" });
 						DomUtil.insertVariable(doc, indexResource, content, options);
 					} else {
-						urlFunctionData.set(urlFunction, { regExpUrlFunction, dataURI: content });
+						resourceInfos.set(resourceURL, { regExpUrlFunction, dataURI: content });
 					}
 				}
 			}));
@@ -1055,7 +1055,7 @@ this.SingleFileCore = this.SingleFileCore || (() => {
 					const originalResourceURL = DomUtil.matchURL(urlFunction);
 					const resourceURL = DomUtil.normalizeURL(originalResourceURL);
 					if (resourceURL && resourceURL != baseURI && DomUtil.testValidPath(resourceURL) && cssText.includes(urlFunction)) {
-						const resourceInfo = urlFunctionData.get(urlFunction);
+						const resourceInfo = resourceInfos.get(resourceURL);
 						if (options.groupDuplicateImages && resourceInfo.variableName) {
 							cssText = cssText.replace(resourceInfo.regExpUrlFunction, resourceInfo.variableName);
 						} else {