Do bounds-checking on more windows (#4797)

Co-authored-by: pajlada <rasmus.karlsson@pajlada.com>

src/widgets/settingspages/AboutPage.cpp

@@ -227,9 +227,13 @@ void AboutPage::addLicense(QFormLayout *form, const QString &name,
     auto *b = new QLabel("<a href=\"" + licenseLink + "\">show license</a>");
     QObject::connect(
         b, &QLabel::linkActivated, [parent = this, name, licenseLink] {
-            auto window = new BasePopup({BaseWindow::Flags::EnableCustomFrame,
-                                         BaseWindow::DisableLayoutSave},
-                                        parent);
+            auto *window = new BasePopup(
+                {
+                    BaseWindow::EnableCustomFrame,
+                    BaseWindow::DisableLayoutSave,
+                    BaseWindow::BoundsCheckOnShow,
+                },
+                parent);
             window->setWindowTitle("Chatterino - License for " + name);
             window->setAttribute(Qt::WA_DeleteOnClose);
             auto layout = new QVBoxLayout();

src/widgets/settingspages/FiltersPage.cpp

@@ -45,9 +45,8 @@ FiltersPage::FiltersPage()
     });
 
     // We can safely ignore this signal connection since we own the view
-    std::ignore = view->addButtonPressed.connect([] {
-        ChannelFilterEditorDialog d(
-            static_cast<QWidget *>(&(getApp()->windows->getMainWindow())));
+    std::ignore = view->addButtonPressed.connect([this] {
+        ChannelFilterEditorDialog d(this->window());
         if (d.exec() == QDialog::Accepted)
         {
             getSettings()->filterRecords.append(