[PyQt] Ubuntu Taskbar icon shows title as "Unknown" while hover

[davidmuni]

Hi all,
I am a new user in python and Qt. I did a small application using PyQt5. It is really wonderful tool. It is working awesome. I face a small issue in ubuntu. I am using FBS to build my App. App and its functionality are working fine in ubuntu.

app.setWindowTitle("my first app")

I am using the following line in my code. it shows the title in my app title bar but the title is not showing in the following places

while I move the cursor over my app icon in ubuntu sidebar, its hover says "unknown"
while I press alt+tab it shows my app icon with the "unknown" as the title.

Guide me to get my App title in those places