After my testing and discussion with the OP in chat, it reveals that the problem is actually a theme related bug. There are different reports of this bug and a workaround is changing the default theme. Here is one of the bug report.
But it needed test to check which themes work. Some theme seem to not working and some does work. After further test, I curated this list of themes that fix the issue.
- Arc Theme
- Arc Flatabulous Theme
- Ceti 2 theme
- Vertext theme
- Menda and Menda Dark theme
- Paper theme
- Adwaita theme
You can find these themes by searching. Here is a link of Noobslab PPA, who has some good collection of themes
To install themes from the PPA. first add it using this two commands
sudo add-apt-repository ppa:noobslab/themes
sudo apt-get update
Then install it by
sudo apt-get install <theme-name-here>