diff --git a/plugins/line-numbers/prism-line-numbers.js b/plugins/line-numbers/prism-line-numbers.js
index 09dc2c773a..dea8e3a801 100644
--- a/plugins/line-numbers/prism-line-numbers.js
+++ b/plugins/line-numbers/prism-line-numbers.js
@@ -83,7 +83,7 @@
 
 		if (clsReg.test(env.element.className)) {
 			// Remove the class "line-numbers" from the <code>
-			env.element.className = env.element.className.replace(clsReg, '');
+			env.element.className = env.element.className.replace(clsReg, ' ');
 		}
 		if (!clsReg.test(pre.className)) {
 			// Add the class "line-numbers" to the <pre>
diff --git a/plugins/unescaped-markup/prism-unescaped-markup.js b/plugins/unescaped-markup/prism-unescaped-markup.js
index ab3059a745..ad1eb63aad 100644
--- a/plugins/unescaped-markup/prism-unescaped-markup.js
+++ b/plugins/unescaped-markup/prism-unescaped-markup.js
@@ -22,6 +22,14 @@
 
 			pre.className = code.className = env.element.className;
 
+			if (env.element.dataset) {
+				Object.keys(env.element.dataset).forEach(function (key) {
+					if (Object.prototype.hasOwnProperty.call(env.element.dataset, key)) {
+						pre.dataset[key] = env.element.dataset[key];
+					}
+				});
+			}
+
 			env.code = env.code.replace(/&lt;\/script(>|&gt;)/gi, "</scri" + "pt>");
 			code.textContent = env.code;