Improve terminal theming, cursor UX, and size negotiation

src/session_tab.cpp

@@ -79,6 +79,11 @@ SessionTab::SessionTab(const Profile& profile, QWidget* parent)
             m_backend,
             &SessionBackend::confirmHostKey,
             Qt::QueuedConnection);
+    connect(this,
+            &SessionTab::requestTerminalSize,
+            m_backend,
+            &SessionBackend::updateTerminalSize,
+            Qt::QueuedConnection);
 
     connect(m_backend,
             &SessionBackend::stateChanged,
@@ -172,6 +177,11 @@ void SessionTab::onCopyErrorClicked()
 void SessionTab::onClearTerminalClicked()
 {
     m_terminalOutput->clear();
+    if (m_state == SessionState::Connected) {
+        // Ask the remote shell to repaint a prompt after local clear.
+        emit requestInput(QStringLiteral("\x0c"));
+    }
+    m_terminalOutput->setFocus();
 }
 
 void SessionTab::onBackendStateChanged(SessionState state, const QString& message)
@@ -339,6 +349,10 @@ void SessionTab::setupUi()
             &TerminalView::inputGenerated,
             this,
             [this](const QString& input) { emit requestInput(input); });
+    connect(m_terminalOutput,
+            &TerminalView::terminalSizeChanged,
+            this,
+            [this](int columns, int rows) { emit requestTerminalSize(columns, rows); });
     connect(m_themeSelector,
             &QComboBox::currentTextChanged,
             m_terminalOutput,
@@ -493,9 +507,7 @@ void SessionTab::refreshActionButtons()
     m_copyErrorButton->setEnabled(!m_lastError.isEmpty());
 
     m_terminalOutput->setEnabled(isConnected);
-    if (isConnected) {
-        m_terminalOutput->setFocus();
-    }
+    m_terminalOutput->setFocus();
 }
 
 void SessionTab::setPanelExpanded(QToolButton* button,