diff --git a/block.go b/block.go
index 021a54d..b237c7e 100644
--- a/block.go
+++ b/block.go
@@ -102,7 +102,7 @@ func (p *parser) block(out *bytes.Buffer, data []byte) {
 		// }
 		// ```
 		if p.flags&EXTENSION_FENCED_CODE != 0 {
-			if i := p.fencedCode(out, data, true); i > 0 {
+			if i := p.fencedCodeBlock(out, data, true); i > 0 {
 				data = data[i:]
 				continue
 			}
@@ -659,7 +659,10 @@ func isFenceLine(data []byte, syntax *string, oldmarker string, newlineOptional
 	return i + 1, marker // Take newline into account.
 }
 
-func (p *parser) fencedCode(out *bytes.Buffer, data []byte, doRender bool) int {
+// fencedCodeBlock returns the end index if data contains a fenced code block at the beginning,
+// or 0 otherwise. It writes to out if doRender is true, otherwise it has no side effects.
+// If doRender is true, a final newline is mandatory to recognize the fenced code block.
+func (p *parser) fencedCodeBlock(out *bytes.Buffer, data []byte, doRender bool) int {
 	var syntax string
 	beg, marker := isFenceLine(data, &syntax, "", true)
 	if beg == 0 || beg >= len(data) {
@@ -672,7 +675,8 @@ func (p *parser) fencedCode(out *bytes.Buffer, data []byte, doRender bool) int {
 		// safe to assume beg < len(data)
 
 		// check for the end of the code block
-		fenceEnd, _ := isFenceLine(data[beg:], nil, marker, true)
+		newlineOptional := !doRender
+		fenceEnd, _ := isFenceLine(data[beg:], nil, marker, newlineOptional)
 		if fenceEnd != 0 {
 			beg += fenceEnd
 			break
@@ -934,7 +938,7 @@ func (p *parser) quote(out *bytes.Buffer, data []byte) int {
 		// irregardless of any contents inside it
 		for data[end] != '\n' {
 			if p.flags&EXTENSION_FENCED_CODE != 0 {
-				if i := p.fencedCode(out, data[end:], false); i > 0 {
+				if i := p.fencedCodeBlock(out, data[end:], false); i > 0 {
 					// -1 to compensate for the extra end++ after the loop:
 					end += i - 1
 					break
@@ -1384,7 +1388,7 @@ func (p *parser) paragraph(out *bytes.Buffer, data []byte) int {
 
 		// if there's a fenced code block, paragraph is over
 		if p.flags&EXTENSION_FENCED_CODE != 0 {
-			if p.fencedCode(out, current, false) > 0 {
+			if p.fencedCodeBlock(out, current, false) > 0 {
 				p.renderParagraph(out, data[:i])
 				return i
 			}
diff --git a/block_test.go b/block_test.go
index a20f5df..6170e56 100644
--- a/block_test.go
+++ b/block_test.go
@@ -1130,6 +1130,12 @@ func TestFencedCodeBlock(t *testing.T) {
 
 		"Some text before a fenced code block\n``` oz\ncode blocks breakup paragraphs\n```\nSome text in between\n``` oz\nmultiple code blocks work okay\n```\nAnd some text after a fenced code block",
 		"<p>Some text before a fenced code block</p>\n\n<pre><code class=\"language-oz\">code blocks breakup paragraphs\n</code></pre>\n\n<p>Some text in between</p>\n\n<pre><code class=\"language-oz\">multiple code blocks work okay\n</code></pre>\n\n<p>And some text after a fenced code block</p>\n",
+
+		"```\n[]:()\n```\n",
+		"<pre><code>[]:()\n</code></pre>\n",
+
+		"```\n[]:()\n[]:)\n[]:(\n[]:x\n[]:testing\n[:testing\n\n[]:\nlinebreak\n[]()\n\n[]:\n[]()\n```",
+		"<pre><code>[]:()\n[]:)\n[]:(\n[]:x\n[]:testing\n[:testing\n\n[]:\nlinebreak\n[]()\n\n[]:\n[]()\n</code></pre>\n",
 	}
 	doTestsBlock(t, tests, EXTENSION_FENCED_CODE)
 }
diff --git a/markdown.go b/markdown.go
index aea997a..58ba68d 100644
--- a/markdown.go
+++ b/markdown.go
@@ -386,9 +386,9 @@ func MarkdownOptions(input []byte, renderer Renderer, opts Options) []byte {
 }
 
 // first pass:
-// - extract references
-// - expand tabs
 // - normalize newlines
+// - extract references (outside of fenced code blocks)
+// - expand tabs (outside of fenced code blocks)
 // - copy everything else
 func firstPass(p *parser, input []byte) []byte {
 	var out bytes.Buffer
@@ -396,46 +396,46 @@ func firstPass(p *parser, input []byte) []byte {
 	if p.flags&EXTENSION_TAB_SIZE_EIGHT != 0 {
 		tabSize = TAB_SIZE_EIGHT
 	}
-	beg, end := 0, 0
+	beg := 0
 	lastFencedCodeBlockEnd := 0
-	for beg < len(input) { // iterate over lines
-		if end = isReference(p, input[beg:], tabSize); end > 0 {
-			beg += end
-		} else { // skip to the next line
-			end = beg
-			for end < len(input) && input[end] != '\n' && input[end] != '\r' {
-				end++
-			}
-
-			if p.flags&EXTENSION_FENCED_CODE != 0 {
-				// track fenced code block boundaries to suppress tab expansion
-				// inside them:
-				if beg >= lastFencedCodeBlockEnd {
-					if i := p.fencedCode(&out, input[beg:], false); i > 0 {
-						lastFencedCodeBlockEnd = beg + i
-					}
-				}
-			}
-
-			// add the line body if present
-			if end > beg {
-				if end < lastFencedCodeBlockEnd { // Do not expand tabs while inside fenced code blocks.
-					out.Write(input[beg:end])
-				} else {
-					expandTabs(&out, input[beg:end], tabSize)
-				}
-			}
-			out.WriteByte('\n')
-
-			if end < len(input) && input[end] == '\r' {
-				end++
-			}
-			if end < len(input) && input[end] == '\n' {
-				end++
-			}
-
-			beg = end
+	for beg < len(input) {
+		// Find end of this line, then process the line.
+		end := beg
+		for end < len(input) && input[end] != '\n' && input[end] != '\r' {
+			end++
 		}
+
+		if p.flags&EXTENSION_FENCED_CODE != 0 {
+			// track fenced code block boundaries to suppress tab expansion
+			// and reference extraction inside them:
+			if beg >= lastFencedCodeBlockEnd {
+				if i := p.fencedCodeBlock(&out, input[beg:], false); i > 0 {
+					lastFencedCodeBlockEnd = beg + i
+				}
+			}
+		}
+
+		// add the line body if present
+		if end > beg {
+			if end < lastFencedCodeBlockEnd { // Do not expand tabs while inside fenced code blocks.
+				out.Write(input[beg:end])
+			} else if refEnd := isReference(p, input[beg:], tabSize); refEnd > 0 {
+				beg += refEnd
+				continue
+			} else {
+				expandTabs(&out, input[beg:end], tabSize)
+			}
+		}
+
+		if end < len(input) && input[end] == '\r' {
+			end++
+		}
+		if end < len(input) && input[end] == '\n' {
+			end++
+		}
+		out.WriteByte('\n')
+
+		beg = end
 	}
 
 	// empty input?