diff -r 2e7225dbd9b2 -r e254398fcc7c sources/interface.cpp
--- a/sources/interface.cpp	Wed Jan 27 13:08:51 2021 +0200
+++ b/sources/interface.cpp	Wed Jan 27 13:17:11 2021 +0200
@@ -167,7 +167,7 @@
 	m_inputHistory.clear();
 	m_inputHistory.push_back("");
 	m_outputLines.clear();
-	m_outputLines << ColoredLine();
+	m_outputLines.push_back(ColoredLine());
 	m_session.setInterface(this);
 	resetTitle();
 
@@ -304,7 +304,7 @@
 	if (m_outputLines.size() == 1)
 		return;
 
-	m_outputScroll = clamp(m_outputScroll, 0, m_outputLines.size() - 1);
+	m_outputScroll = clamp(m_outputScroll, 0, static_cast<signed>(m_outputLines.size() - 1));
 
 	int height = LINES - 3;
 	int width = COLS - nicklistWidth();
@@ -334,7 +334,7 @@
 	// See if there's any more rows to use(end may be too small)
 	if (not tightFit)
 	{
-		while (end < m_outputLines.size())
+		while (end < static_cast<int>(m_outputLines.size()))
 		{
 			int rows = m_outputLines[end].rows(width);
 
@@ -963,12 +963,12 @@
 	{
 		if (ch == '\n')
 		{
-			m_outputLines.last().finalize();
-			m_outputLines << ColoredLine();
+			zfc::last(m_outputLines).finalize();
+			m_outputLines.push_back({});
 			continue;
 		}
 
-		if (m_outputLines.last().length() == 0)
+		if (zfc::last(m_outputLines).length() == 0)
 		{
 			time_t now;
 			time(&now);
@@ -976,14 +976,14 @@
 			strftime(timestamp, sizeof timestamp, "[%H:%M:%S] ", localtime(&now));
 
 			for (char ch : String(timestamp))
-				m_outputLines.last().addChar(ch);
+				zfc::last(m_outputLines).addChar(ch);
 		}
 
 		// Remove some lines if there's too many of them. 20,000 should be enough, I hope.
 		while (m_outputLines.size() > 20000)
-			m_outputLines.remove_at(0);
+			m_outputLines.erase(m_outputLines.begin());
 
-		m_outputLines.last().addChar(ch);
+		zfc::last(m_outputLines).addChar(ch);
 	}
 
 	m_needOutputRender = true;