diff --git a/src/Converter/HtmlToDjot.php b/src/Converter/HtmlToDjot.php
index 1d881af..90aa295 100644
--- a/src/Converter/HtmlToDjot.php
+++ b/src/Converter/HtmlToDjot.php
@@ -970,6 +970,22 @@ protected function processLink(DOMElement $node): string
             // Skip href, title, and data-djot-ref since they're in the reference syntax
             $attrs = $this->formatInlineAttributes($node, ['href', 'title', 'data-djot-ref']);
 
+            if ($refLabel === '' && !$this->isSafeReferenceLabel($text)) {
+                if ($title !== '') {
+                    return '[' . $text . '](' . $href . ' ' . $this->quoteLinkTitle($title) . ')' . $attrs;
+                }
+
+                return '[' . $text . '](' . $href . ')' . $attrs;
+            }
+
+            if ($refLabel !== '' && !$this->isSafeReferenceLabel($refLabel)) {
+                if ($title !== '') {
+                    return '[' . $text . '](' . $href . ' ' . $this->quoteLinkTitle($title) . ')' . $attrs;
+                }
+
+                return '[' . $text . '](' . $href . ')' . $attrs;
+            }
+
             // Collect reference definition
             // For collapsed reference (empty label), use the link text as label
             $defLabel = $refLabel === '' ? $text : $refLabel;
@@ -1014,6 +1030,22 @@ protected function processImage(DOMElement $node): string
             // Skip src, alt, title, and data-djot-ref since they're in the reference syntax
             $attrs = $this->formatInlineAttributes($node, ['src', 'alt', 'title', 'data-djot-ref']);
 
+            if ($refLabel === '' && !$this->isSafeReferenceLabel($alt)) {
+                if ($title !== '') {
+                    return '![' . $alt . '](' . $src . ' ' . $this->quoteLinkTitle($title) . ')' . $attrs;
+                }
+
+                return '![' . $alt . '](' . $src . ')' . $attrs;
+            }
+
+            if ($refLabel !== '' && !$this->isSafeReferenceLabel($refLabel)) {
+                if ($title !== '') {
+                    return '![' . $alt . '](' . $src . ' ' . $this->quoteLinkTitle($title) . ')' . $attrs;
+                }
+
+                return '![' . $alt . '](' . $src . ')' . $attrs;
+            }
+
             // Collect reference definition
             // For collapsed reference (empty label), use the alt text as label
             $defLabel = $refLabel === '' ? $alt : $refLabel;
@@ -1551,7 +1583,9 @@ protected function serializeTableCellContent(DOMElement $cell): string
         $content = $hasBlockChildren ? $this->processBlock($cell) : $this->processChildren($cell);
         $content = trim($content);
 
-        return preg_replace('/\s+/', ' ', $content) ?? $content;
+        $content = preg_replace('/\s+/', ' ', $content) ?? $content;
+
+        return str_replace('|', '\|', $content);
     }
 
     protected function findFirstDirectChildByTagName(DOMElement $node, string $tagName): ?DOMElement
@@ -1729,7 +1763,12 @@ protected function processRawInline(DOMElement $node): string
 
     protected function processRawHtmlInlineElement(DOMElement $node): string
     {
-        $html = $node->ownerDocument?->saveHTML($node);
+        $clone = $node->cloneNode(true);
+        if ($clone instanceof DOMElement) {
+            $this->stripDjotDataAttributes($clone);
+        }
+
+        $html = $clone instanceof DOMElement ? $clone->ownerDocument?->saveHTML($clone) : null;
         if (!is_string($html)) {
             $html = '';
         }
@@ -1754,6 +1793,32 @@ protected function linkRequiresRawHtmlFallback(DOMElement $node): bool
         return false;
     }
 
+    protected function isSafeReferenceLabel(string $label): bool
+    {
+        return strpbrk($label, '[]\\') === false;
+    }
+
+    protected function stripDjotDataAttributes(DOMElement $node): void
+    {
+        $toRemove = [];
+        /** @var \DOMAttr $attr */
+        foreach ($node->attributes as $attr) {
+            if (str_starts_with($attr->name, 'data-djot-')) {
+                $toRemove[] = $attr->name;
+            }
+        }
+
+        foreach ($toRemove as $name) {
+            $node->removeAttribute($name);
+        }
+
+        foreach ($node->childNodes as $child) {
+            if ($child instanceof DOMElement) {
+                $this->stripDjotDataAttributes($child);
+            }
+        }
+    }
+
     /**
      * Process semantic HTML elements to Djot span syntax
      *
diff --git a/tests/TestCase/Converter/HtmlToDjotTest.php b/tests/TestCase/Converter/HtmlToDjotTest.php
index b86a97f..99abfe0 100644
--- a/tests/TestCase/Converter/HtmlToDjotTest.php
+++ b/tests/TestCase/Converter/HtmlToDjotTest.php
@@ -148,6 +148,23 @@ public function testLinkEscapesBackslashInLabel(): void
         $this->assertStringContainsString('<a href="https://example.com">a \ b</a>', $htmlBack);
     }
 
+    public function testCollapsedReferenceLinkWithUnsafeLabelFallsBackToInlineLink(): void
+    {
+        $result = $this->converter->convert('<a href="https://example.com" data-djot-ref="">a ] b</a>');
+
+        $this->assertSame("[a \\] b](https://example.com)\n", $result);
+        $this->assertStringNotContainsString("\n[a \\] b]:", $result);
+    }
+
+    public function testReferenceLinkWithUnsafeReferenceLabelFallsBackToInlineLink(): void
+    {
+        $result = $this->converter->convert('<a href="https://example.com" data-djot-ref="ref]x">txt</a>');
+
+        $this->assertSame("[txt](https://example.com)\n", $result);
+        $this->assertStringNotContainsString('[txt][', $result);
+        $this->assertStringNotContainsString("\n[ref]x]:", $result);
+    }
+
     // ==================== Images ====================
 
     public function testImage(): void
@@ -195,6 +212,14 @@ public function testLinkWrappingProblematicImageFallsBackToRawHtml(): void
         $this->assertStringContainsString('<a href="https://example.com"><img src="img.png" alt="a [ b"></a>', $htmlBack);
     }
 
+    public function testRawImageFallbackStripsDjotMetadata(): void
+    {
+        $result = $this->converter->convert('<img src="img.png" alt="a [ b" data-djot-ref="">');
+
+        $this->assertSame("`<img src=\"img.png\" alt=\"a [ b\">`{=html}\n", $result);
+        $this->assertStringNotContainsString('data-djot-ref', $result);
+    }
+
     // ==================== Code ====================
 
     public function testInlineCode(): void
@@ -342,8 +367,8 @@ public function testNestedTableDoesNotLeakInnerRowsIntoOuterTable(): void
 
         $result = $this->converter->convert($html);
 
-        $this->assertStringContainsString('| outer', $result);
-        $this->assertSame(1, substr_count($result, '| inner |'));
+        $this->assertSame("| outer \\| inner \\| |\n", $result);
+        $this->assertStringNotContainsString("\n| inner |", $result);
     }
 
     public function testDivWithoutClassPreservesAttributes(): void
@@ -543,6 +568,27 @@ public function testTableCellWithNestedListFallsBackToSingleLineCellText(): void
         $this->assertStringContainsString('<td>- Item</td>', $htmlBack);
     }
 
+    public function testTableCellEscapesLiteralPipeCharacters(): void
+    {
+        $html = '<table><tr><td>A | B</td></tr></table>';
+        $result = $this->converter->convert($html);
+
+        $this->assertSame("| A \\| B |\n", $result);
+        $htmlBack = (new DjotConverter())->convert($result);
+        $this->assertStringContainsString('<td>A | B</td>', $htmlBack);
+        $this->assertStringNotContainsString('<td>A</td>', $htmlBack);
+    }
+
+    public function testTableCellEscapesPipeCharactersAfterBlockDegradation(): void
+    {
+        $html = '<table><tr><td><p>A | B</p><p>C</p></td></tr></table>';
+        $result = $this->converter->convert($html);
+
+        $this->assertSame("| A \\| B C |\n", $result);
+        $htmlBack = (new DjotConverter())->convert($result);
+        $this->assertStringContainsString('<td>A | B C</td>', $htmlBack);
+    }
+
     public function testTableWithMultilineCaptionKeepsAllCaptionTextInsideCaption(): void
     {
         $html = '<table><caption><p>cap one</p><p>cap two</p></caption><tr><td>x</td></tr></table>';