@payman
i have no experience with accessibility on Linux. But maybe the following helps you:
Qt Accessibility is based on AT-SPI via DBus on Unix/X11 and is tested to be working on Gnome and KDE.
Are you sure that i3wm even supports accessibility?
Actually I have since spotted what the problem was, As it turns out creating a new instance of QNetworkAccessManager every 15 seconds is not the best idea if you're not deleting them.
The solution I went with was making *manager a class member.