fix regression with svg sprites (fix #792)

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

@@ -1912,27 +1912,26 @@ class ProcessorHelper {
 				}
 				if (testValidURL(resourceURL)) {
 					const hashMatch = originalResourceURL.match(REGEXP_URL_HASH);
-					if (hashMatch && hashMatch[0]) {
-						if (originalResourceURL.startsWith(baseURI + "#")) {
-							resourceElement.setAttribute(attributeName, hashMatch[0]);
-						} else {
-							const response = await batchRequest.addURL(resourceURL);
-							const svgDoc = util.parseSVGContent(response.content);
+					if (originalResourceURL.startsWith(baseURI + "#")) {
+						resourceElement.setAttribute(attributeName, hashMatch[0]);
+					} else {
+						const response = await batchRequest.addURL(resourceURL);
+						const svgDoc = util.parseSVGContent(response.content);
+						if (hashMatch && hashMatch[0]) {
+							let symbolElement;
 							try {
-								const spriteElement = svgDoc.querySelector(hashMatch[0]);
-								if (spriteElement.tagName.toLowerCase() == "symbol") {
-									resourceElement.after(...spriteElement.childNodes);
-									resourceElement.remove();
-								} else {
-									resourceElement.parentElement.replaceChild(spriteElement, resourceElement);
-								}
+								symbolElement = svgDoc.querySelector(hashMatch[0]);
 							} catch (error) {
 								// ignored
 							}
+							if (symbolElement) {
+								resourceElement.setAttribute(attributeName, hashMatch[0]);
+								resourceElement.parentElement.insertBefore(symbolElement, resourceElement.parentElement.firstChild);
+							}
+						} else {
+							const content = await batchRequest.addURL(resourceURL);
+							resourceElement.setAttribute(attributeName, PREFIX_DATA_URI_IMAGE_SVG + "," + content);
 						}
-					} else {
-						const content = await batchRequest.addURL(resourceURL);
-						resourceElement.setAttribute(attributeName, PREFIX_DATA_URI_IMAGE_SVG + "," + content);
 					}
 				}
 			} else if (resourceURL == options.url) {