fix: About window now is a dialog

ui/widgets/about.cpp

@@ -25,7 +25,7 @@ static const std::string QXMPP_VERSION_MAJOR(std::to_string(QXMPP_VERSION >> 16)
 static const QString QXMPP_VERSION_STRING = QString::fromStdString(QXMPP_VERSION_MAJOR + "." + QXMPP_VERSION_MINOR + "." + QXMPP_VERSION_PATCH);
 
 About::About(QWidget* parent):
-    QWidget(parent),
+    QDialog(parent),
     m_ui(new Ui::About),
     license(nullptr)
 {
@@ -37,7 +37,11 @@ About::About(QWidget* parent):
     m_ui->qxmppVersionValue->setText(QXmppVersion());
     m_ui->qxmppBuiltAgainstVersion->setText(tr("(built against %1)").arg(QXMPP_VERSION_STRING));
 
-    setWindowFlag(Qt::Tool);
+    setWindowFlag(Qt::WindowStaysOnTopHint);
+    move(
+          parent->window()->frameGeometry().topLeft() +
+          parent->window()->rect().center() - rect().center()
+       );
 
     connect(m_ui->licenceLink, &QLabel::linkActivated, this, &About::onLicenseActivated);
 }

ui/widgets/about.h

@@ -17,7 +17,7 @@
 #ifndef ABOUT_H
 #define ABOUT_H
 
-#include <QWidget>
+#include <QDialog>
 #include <QScopedPointer>
 #include <QApplication>
 #include <QFile>
@@ -32,7 +32,7 @@ class About;
 /**
  * @todo write docs
  */
-class About : public QWidget
+class About : public QDialog
 {
     Q_OBJECT
 public: