diff --git a/converter/fuzz_test.go b/converter/fuzz_test.go
index 72c3020..94e9a86 100644
--- a/converter/fuzz_test.go
+++ b/converter/fuzz_test.go
@@ -61,6 +61,20 @@ func FuzzPreProcessHTML(f *testing.F) {
 		`<td><p>Paragraph in cell</p></td>`,
 		`<div class="table-wrap"><table><tr><td>Cell</td></tr></table></div>`,
 
+		// Lists inside table cells (issue #6) and header-row promotion
+		`<table><tbody><tr><th>H1</th><th>H2</th></tr><tr><td>intro:<ul><li>a</li><li>b</li></ul></td><td>x</td></tr></tbody></table>`,
+		`<table><tbody><tr><td><ol><li>one</li><li>two</li></ol></td></tr></tbody></table>`,
+		`<td><ul><li></li><li></li><li>  </li></ul></td>`,
+		`<td>top<ul><li>a<ul><li>nested</li></ul></li><li>b</li></ul></td>`,
+		`<table><tbody><tr><th>H</th><td>d</td></tr><tr><td>a</td><td>b</td></tr></tbody></table>`,
+		`<table><tbody><tr><th>Only</th></tr></tbody></table>`,
+		`<ul><li>unclosed list item`,
+		`<ul><li>a</li><li>b`,
+		`<table><tr><th>x</th><ul><li>malformed</li></ul></tr></table>`,
+		strings.Repeat(`<li></li>`, 100),
+		`<td>literal @@C2MDBR@@ sentinel</td>`,
+		`<table><tbody><tr><td><ul><li><strong>b</strong></li><li><a href="u">l</a></li></ul></td></tr></tbody></table>`,
+
 		// Spans (various classes)
 		`<span class="nolink">No link text</span>`,
 		`<span class="status-macro aui-lozenge">STATUS</span>`,
@@ -208,6 +222,12 @@ func FuzzPostProcessMarkdown(f *testing.F) {
 		"Line 1<br/>Line 2",
 		"Line 1<br />Line 2",
 
+		// Intra-cell line-break sentinel (restored to <br> by post-processing)
+		"| a" + cellLineBreakSentinel + "b |",
+		cellLineBreakSentinel,
+		"text " + cellLineBreakSentinel + " more",
+		strings.Repeat(cellLineBreakSentinel, 100),
+
 		// Multiple newlines
 		"Line 1\n\n\n\n\nLine 2",
 
diff --git a/converter/markdown.go b/converter/markdown.go
index 7ead8e5..c877f51 100644
--- a/converter/markdown.go
+++ b/converter/markdown.go
@@ -200,6 +200,10 @@ func decodeHTMLEntities(html string) string {
 // preProcessHTML removes Confluence layout markup before Pandoc conversion.
 // This ensures layout divs don't get escaped and pollute the output.
 func preProcessHTML(html string) string {
+	// Neutralize any pre-existing occurrence of our internal sentinel so that
+	// source content can never inject an intra-cell line break (see flattenCellLists).
+	html = strings.ReplaceAll(html, cellLineBreakSentinel, "")
+
 	// First, decode HTML entities that represent actual HTML tags
 	// Confluence sometimes double-encodes HTML, resulting in &lt;p&gt; instead of <p>
 	html = decodeHTMLEntities(html)
@@ -375,20 +379,29 @@ func preProcessHTML(html string) string {
 // Limitation: nested sub-lists are flattened to a single bullet level (their items
 // are still preserved as text, just without indentation).
 func flattenCellLists(inner string) string {
-	// Ordered lists first so their items get numbers rather than bullets.
+	// Ordered lists first so their items get numbers rather than bullets. Empty
+	// items are dropped so they don't leave a stray "N. " with no text.
 	inner = cellOrderedListPattern.ReplaceAllStringFunc(inner, func(block string) string {
 		n := 0
 		items := cellListItemPattern.ReplaceAllStringFunc(block, func(li string) string {
+			text := cleanListItemText(li)
+			if text == "" {
+				return ""
+			}
 			n++
-			return fmt.Sprintf("%s%d. %s", cellLineBreakSentinel, n, cleanListItemText(li))
+			return fmt.Sprintf("%s%d. %s", cellLineBreakSentinel, n, text)
 		})
 		return cellListTagPattern.ReplaceAllString(items, "")
 	})
 
-	// Unordered lists.
+	// Unordered lists (empty items dropped).
 	inner = cellUnorderedListPattern.ReplaceAllStringFunc(inner, func(block string) string {
 		items := cellListItemPattern.ReplaceAllStringFunc(block, func(li string) string {
-			return cellLineBreakSentinel + "• " + cleanListItemText(li)
+			text := cleanListItemText(li)
+			if text == "" {
+				return ""
+			}
+			return cellLineBreakSentinel + "• " + text
 		})
 		return cellListTagPattern.ReplaceAllString(items, "")
 	})
@@ -396,7 +409,11 @@ func flattenCellLists(inner string) string {
 	// Defensive: bullet any <li> not wrapped in a recognized list, then drop any
 	// leftover list container/item tags so none survive into pandoc.
 	inner = cellListItemPattern.ReplaceAllStringFunc(inner, func(li string) string {
-		return cellLineBreakSentinel + "• " + cleanListItemText(li)
+		text := cleanListItemText(li)
+		if text == "" {
+			return ""
+		}
+		return cellLineBreakSentinel + "• " + text
 	})
 	inner = cellListTagPattern.ReplaceAllString(inner, "")
 	inner = cellListItemTagPattern.ReplaceAllString(inner, "")
@@ -414,8 +431,8 @@ func promoteTableHeaderRows(html string) string {
 			return table // already has an explicit header
 		}
 		firstRow := tableRowPattern.FindString(table)
-		if firstRow == "" || !strings.Contains(firstRow, "<th>") {
-			return table // first row is not a header row; leave as-is
+		if firstRow == "" || !strings.Contains(firstRow, "<th>") || strings.Contains(firstRow, "<td>") {
+			return table // promote only a genuine, all-<th> header row
 		}
 		// Lift the first row out of the body and into a <thead> after <table>.
 		rest := strings.Replace(table, firstRow, "", 1)
diff --git a/converter/markdown_test.go b/converter/markdown_test.go
index 03579f3..c596432 100644
--- a/converter/markdown_test.go
+++ b/converter/markdown_test.go
@@ -1010,6 +1010,133 @@ func TestPreProcessHTML_PromoteHeaderRow_KeepsExistingThead(t *testing.T) {
 	}
 }
 
+// --- Phase 1 (TDD): edge cases expected to fail against the current code ---
+
+func TestFlattenCellLists_DropsEmptyItems(t *testing.T) {
+	// Empty or whitespace-only <li> items must not produce stray empty bullets.
+	input := `<table><tbody><tr><td><ul><li></li><li>x</li><li>  </li></ul></td></tr></tbody></table>`
+
+	result := preProcessHTML(input)
+
+	if !strings.Contains(result, "<td>• x</td>") {
+		t.Errorf("Expected a single non-empty bullet (<td>• x</td>), got: %s", result)
+	}
+}
+
+func TestPreProcessHTML_SentinelCollisionNeutralized(t *testing.T) {
+	// User content that literally contains the internal sentinel must not be able
+	// to inject a line break; the sentinel should be stripped from the input.
+	input := `<p>literal ` + cellLineBreakSentinel + ` text</p>`
+
+	result := preProcessHTML(input)
+
+	if strings.Contains(result, cellLineBreakSentinel) {
+		t.Errorf("Expected pre-existing sentinel to be neutralized, got: %s", result)
+	}
+}
+
+func TestPreProcessHTML_MixedHeaderRowNotPromoted(t *testing.T) {
+	// A first row mixing <th> and <td> is not a genuine header row and must not
+	// be lifted into <thead>.
+	input := `<table><tbody><tr><th>H</th><td>d</td></tr><tr><td>a</td><td>b</td></tr></tbody></table>`
+
+	result := preProcessHTML(input)
+
+	if strings.Contains(result, "<thead>") {
+		t.Errorf("Expected a mixed th/td first row NOT to be promoted, got: %s", result)
+	}
+}
+
+// --- Phase 3 (TDD): regression locks for behavior that should already be correct ---
+
+func TestFlattenCellLists_OrderedListsRestartNumbering(t *testing.T) {
+	// Two separate ordered lists in one cell must each restart numbering at 1.
+	input := `<table><tbody><tr><td><ol><li>a</li><li>b</li></ol><ol><li>c</li><li>d</li></ol></td></tr></tbody></table>`
+
+	result := preProcessHTML(input)
+
+	for _, want := range []string{"1. a", "2. b", "1. c", "2. d"} {
+		if !strings.Contains(result, want) {
+			t.Errorf("Expected %q in numbered output, got: %s", want, result)
+		}
+	}
+}
+
+func TestFlattenCellLists_OrderedEmptyItemAndStrayLi(t *testing.T) {
+	// Covers: an empty <li> in an ordered list (skipped, numbering not consumed),
+	// and stray <li> elements outside any recognized list (bulleted / dropped).
+	input := `<table><tbody><tr><td><ol><li></li><li>keep</li></ol><li>stray</li><li></li></td></tr></tbody></table>`
+
+	result := preProcessHTML(input)
+
+	if !strings.Contains(result, "1. keep") {
+		t.Errorf("Expected ordered numbering to skip the empty item, got: %s", result)
+	}
+	if !strings.Contains(result, "• stray") {
+		t.Errorf("Expected stray <li> to be bulleted, got: %s", result)
+	}
+	if strings.Contains(result, "<li") || strings.Contains(result, "<ol") {
+		t.Errorf("Expected no list tags to survive, got: %s", result)
+	}
+}
+
+func TestPreProcessHTML_MultipleTablesHeaderPromotion(t *testing.T) {
+	// Every table in the document with a pure header row should be promoted.
+	input := `<table><tbody><tr><th>A</th></tr><tr><td>1</td></tr></tbody></table>` +
+		`<table><tbody><tr><th>B</th></tr><tr><td>2</td></tr></tbody></table>`
+
+	result := preProcessHTML(input)
+
+	if got := strings.Count(result, "<thead>"); got != 2 {
+		t.Errorf("Expected both tables promoted (2 <thead>), got %d: %s", got, result)
+	}
+}
+
+func TestConvertHTMLToMarkdown_ListItemInlineFormatting(t *testing.T) {
+	// Inline formatting and links inside list items must survive into Markdown.
+	if err := CheckPandoc(); err != nil {
+		t.Skipf("Pandoc not installed, skipping test: %v", err)
+	}
+
+	html := `<table><tbody><tr><th>H</th></tr>` +
+		`<tr><td><ul><li><strong>bold</strong></li><li><a href="https://ex.com">link</a></li></ul></td></tr></tbody></table>`
+
+	md, err := ConvertHTMLToMarkdown(html)
+	if err != nil {
+		t.Fatalf("ConvertHTMLToMarkdown failed: %v", err)
+	}
+
+	if strings.Contains(md, "<table") || strings.Contains(md, "<ul") {
+		t.Errorf("Expected a Markdown table (no raw HTML), got: %s", md)
+	}
+	for _, want := range []string{"• **bold**", "• [link](https://ex.com)"} {
+		if !strings.Contains(md, want) {
+			t.Errorf("Expected %q, got: %s", want, md)
+		}
+	}
+}
+
+func TestConvertHTMLToMarkdown_HeaderOnlyTable(t *testing.T) {
+	// A table whose only row is a header must convert without crashing or falling
+	// back to raw HTML.
+	if err := CheckPandoc(); err != nil {
+		t.Skipf("Pandoc not installed, skipping test: %v", err)
+	}
+
+	html := `<table><tbody><tr><th>Only</th><th>Header</th></tr></tbody></table>`
+
+	md, err := ConvertHTMLToMarkdown(html)
+	if err != nil {
+		t.Fatalf("ConvertHTMLToMarkdown failed: %v", err)
+	}
+	if strings.Contains(md, "<table") {
+		t.Errorf("Expected a Markdown table (no raw HTML), got: %s", md)
+	}
+	if !strings.Contains(md, "Only") || !strings.Contains(md, "Header") {
+		t.Errorf("Expected header content preserved, got: %s", md)
+	}
+}
+
 func TestPostProcessMarkdown_CellLineBreakSentinel(t *testing.T) {
 	input := "| left side:" + cellLineBreakSentinel + "• foo" + cellLineBreakSentinel + "• bar | right side |"