fix: long threads out of bounds

tui.go

@@ -1906,6 +1906,12 @@ func (m App) dashboardMaxScroll() int {
 }
 
 func (m App) detailPaneSize() (int, int) {
+	if m.contentTop == 0 &&
+		len(m.difflet.frameLines()) == diffletHeight &&
+		!m.diffletHiddenForCurrentView() &&
+		m.screen != dashboardScreen {
+		m, _ = m.diffletContentModel()
+	}
 	topLines := m.threadTopLineCount()
 	height := max(3, m.height-topLines-1)
 	if m.width < 70 || m.listHidden {
@@ -1958,20 +1964,39 @@ func (m App) View() string {
 	if m.screen == dashboardScreen {
 		return m.viewDashboardWithLines(m.dashboardLinesWithDifflet(mascot))
 	}
-	gap := diffletGap
+	content, hasHeader := m.diffletContentModel()
+	if !hasHeader {
+		return lipgloss.NewStyle().Width(m.width).Height(m.height).Render(
+			strings.Join(mascot, "\n") + "\n\n" + content.viewContent(),
+		)
+	}
+	rendered := content.viewContent()
+	header, body, ok := splitHeader(rendered)
+	if !ok {
+		return lipgloss.NewStyle().Width(m.width).Height(m.height).Render(
+			strings.Join(mascot, "\n") + "\n\n" + rendered,
+		)
+	}
+	headerBand := renderHeaderWithDifflet(
+		header, mascot, m.width, content.headerWidth, diffletGap,
+	)
+	return lipgloss.NewStyle().Width(m.width).Height(m.height).Render(
+		headerBand + "\n\n" + body,
+	)
+}
+
+func (m App) diffletContentModel() (content App, hasHeader bool) {
 	headerWidth := diffletHeaderWidth(m.width)
 	if headerWidth < 1 {
 		headerWidth = m.width
 	}
-	content := m
+	content = m
 	content.headerWidth = headerWidth
 	headerLineCount, hasHeader := content.diffletHeaderLineCount()
 	if !hasHeader {
 		content.height = max(1, m.height-diffletHeight-1)
 		content.contentTop = diffletHeight + 1
-		return lipgloss.NewStyle().Width(m.width).Height(m.height).Render(
-			strings.Join(mascot, "\n") + "\n\n" + content.viewContent(),
-		)
+		return content, hasHeader
 	}
 	bandHeight := max(diffletHeight, headerLineCount)
 	addedRows := bandHeight - headerLineCount
@@ -1980,17 +2005,7 @@ func (m App) View() string {
 	}
 	content.height = max(1, m.height-addedRows)
 	content.contentTop = addedRows
-	rendered := content.viewContent()
-	header, body, ok := splitHeader(rendered)
-	if !ok {
-		return lipgloss.NewStyle().Width(m.width).Height(m.height).Render(
-			strings.Join(mascot, "\n") + "\n\n" + rendered,
-		)
-	}
-	headerBand := renderHeaderWithDifflet(header, mascot, m.width, headerWidth, gap)
-	return lipgloss.NewStyle().Width(m.width).Height(m.height).Render(
-		headerBand + "\n\n" + body,
-	)
+	return content, hasHeader
 }
 
 func (m App) diffletHiddenForCurrentView() bool {