* Remove unused VRAM dump option

* Only emit fileSelected signal if the user didn't cancel file selection
* Don't unmount emulator images if the user cancelled file selection

src/qt/qt_filefield.cpp

@@ -30,7 +30,9 @@ void FileField::on_pushButton_clicked() {
         fileName = QFileDialog::getOpenFileName(this, QString(), QString(), filter_, &selectedFilter_);
     }
 
-    fileName_ = fileName;
-    ui->label->setText(fileName);
-    emit fileSelected(fileName);
+    if (!fileName.isNull()) {
+        fileName_ = fileName;
+        ui->label->setText(fileName);
+        emit fileSelected(fileName);
+    }
 }

src/qt/qt_mainwindow.cpp

@@ -384,21 +384,6 @@ MainWindow::MainWindow(QWidget *parent) :
         });
     }
 #endif
-
-#ifdef ENABLE_VRAM_DUMP
-    {
-#ifndef MTR_ENABLED
-        ui->menuTools->addSeparator();
-#endif
-        auto actionDump_video_RAM = ui->menuTools->addAction(tr("Dump &video RAM"));
-        actionDump_video_RAM->setShortcut(QKeySequence(Qt::Key_Control + Qt::Key_F1));
-#ifdef Q_OS_MACOS
-        actionDump_video_RAM->setShortcutVisibleInContextMenu(true);
-#endif
-        connect(actionDump_video_RAM, &QAction::triggered, this, [this]
-        { svga_dump_vram(); });
-    }
-#endif
 }
 
 void MainWindow::closeEvent(QCloseEvent *event) {

src/qt/qt_mediamenu.cpp

@@ -143,7 +143,10 @@ void MediaMenu::cassetteNewImage() {
     if (fileinfo.suffix().isEmpty()) {
         filename.append(".cas");
     }
-    cassetteMount(filename, false);
+    if (!filename.isNull()) {
+        if (filename.isEmpty()) cassetteEject();
+        else cassetteMount(filename, false);
+    }
 }
 
 void MediaMenu::cassetteSelectImage(bool wp) {
@@ -155,7 +158,7 @@ void MediaMenu::cassetteSelectImage(bool wp) {
         tr("All files") %
         util::DlgFilter({ "*" }, true));
 
-    cassetteMount(filename, wp);
+    if (!filename.isEmpty()) cassetteMount(filename, wp);
 }
 
 void MediaMenu::cassetteMount(const QString& filename, bool wp) {
@@ -276,7 +279,7 @@ void MediaMenu::floppySelectImage(int i, bool wp) {
         tr("All files") %
         util::DlgFilter({ "*" }, true));
 
-    floppyMount(i, filename, wp);
+    if (!filename.isEmpty()) floppyMount(i, filename, wp);
 }
 
 void MediaMenu::floppyMount(int i, const QString &filename, bool wp) {
@@ -349,8 +352,6 @@ void MediaMenu::cdromMount(int i) {
         util::DlgFilter({ "*" }, true));
 
     if (filename.isEmpty()) {
-        auto* imageMenu = dynamic_cast<QAction*>(cdromMenus[i]->children()[cdromImagePos]);
-        imageMenu->setChecked(false);
         return;
     }
     QByteArray fn = filename.toUtf8().data();
@@ -439,7 +440,7 @@ void MediaMenu::zipSelectImage(int i, bool wp) {
         tr("All files") %
         util::DlgFilter({ "*" }, true));
 
-    zipMount(i, filename, wp);
+    if (!filename.isEmpty()) zipMount(i, filename, wp);
 }
 
 void MediaMenu::zipMount(int i, const QString &filename, bool wp) {
@@ -536,7 +537,7 @@ void MediaMenu::moSelectImage(int i, bool wp) {
         tr("All files") %
         util::DlgFilter({ "*", }, true));
 
-    moMount(i, filename, wp);
+    if (!filename.isEmpty()) moMount(i, filename, wp);
 }
 
 void MediaMenu::moMount(int i, const QString &filename, bool wp) {