diff --git a/mainwindow.cpp b/mainwindow.cpp
--- a/mainwindow.cpp
+++ b/mainwindow.cpp
@@ -139,6 +139,8 @@ MainWindow::MainWindow(QWidget *parent) 
 
     // init text view
     ui->ptTextView->setEnabled(ui->cbEnableTextView->isChecked());
+    // TODO: does this work in binary mode? (no new lines)
+    ui->ptTextView->setMaximumBlockCount(10000);
     QObject::connect(ui->cbEnableTextView, &QCheckBox::toggled,
                      ui->ptTextView, &QWidget::setEnabled);