Questions[unity-tweak-tool](ubuntu)

I am using Ubuntu 20.04. I wanted to install Unity-tweak-tool, but a few seconds after it began installing I canceled the installation and then an app was added to my launcher and it's mostly like "nautilus" with the name "Files" and a purple icon and different customization and background.

I want to uninstall it or at least remove its icon. I have searched "unity-tweak-tool", "Files" and in /usr/share/applications for its icon to remove and the command: dpkg --list, but none of them exist.

The app's icon and name:

The left one is this new app and right one is nautilus:

Why does Installing Unity Tweak Tool fail with Ubuntu 19.10?

I already did these commands:

sudo apt-get install notify-osd   
sudo apt-get install overlay-scrollbar

This happened right after upgrading to Ubuntu 18.04 on my father's PC from Ubuntu 16.04.

Changing the icon pack or the GTK theme does not work. The only way I get to see the icons again is by disabling auto-coloring based on wallpaper using the Unity Tweak Tool.

Does anyone know why and how it happened? It'd be great if the icons are visible again with the auto-coloring enabled.

I have added the unity-tweak-tools to the unity-control-center as follows:

sudo gedit usr/share/applications/unity-tweak-tools

then completed the line Categories=Settings; as follows and added another line:

Categories=GNOME;GTK;Settings;X-Unity-Settings-Panel;X-GNOME-PersonalSettings;
X-Unity-Settings-Panel=/usr/bin/unity-tweak-tools

It seems to work and the icon is getting shown up in the System Settings window, but after clicking it, nothing happens. Does anybody know the problem?

Thank you in advance

I am trying to toggle the desktop by going to the lower left corner. I used the Hotcorners from the Unity Tweak Tool by setting that corner to "Toggle Desktop" but it doesn't work. The other functions for that corner work as they should though. Why is that happening?

If you have any other alternatives to succeed that feel free to mention them.