unable to install Teensyduino 1.51 onto Arduino IDE 1.8.12

I have an issue installing Teensyduino 1.51 for my Arduino 1.8.12. The problem I'm having is "Checking Arduino 1.8.12: version "lib/version.txt" matches file: "arduino" missing. I'm trying to install this in my Ubuntu 18.04. (linux 64)

The problem might have stemmed from the fact that I downloaded Arduino IDE 1.8.12 straight from the website, removed that and then installed it using the terminal witht the arduino-1.8.12-linx64.tar-xz zip file.

It works here on Ubuntu 18.04. Just extract Arduino's .tar.gz, then run the installer and select the folder where it extracted.

PaulStoffregen said:

It works here on Ubuntu 18.04. Just extract Arduino's .tar.gz, then run the installer and select the folder where it extracted.

Click to expand...

I'm pretty new to the virtual machine. What I'm getting at is this
-extract the Arduino's .tar.gz using the terminal? I've only extracted the .tar.xz previously on the file system and unable to locate where the .tar.gz is
-running the teensyduino installer
- and finally find the directory where it's extracted. Must the extracted file be in the same place as the Arduino file? (the one containing libraries)

PaulStoffregen said:

It works here on Ubuntu 18.04. Just extract Arduino's .tar.gz, then run the installer and select the folder where it extracted.

Click to expand...

So I tried extracting the .tar.gz file using the terminal (that did not work out) but all you have to do is copy over the "arduino" file in the arduino 1.8.12 directory and paste it into the Arduino file containing the libraries. I don't know why I couldn't locate the arduino file yesterday but I feel dumb.