Error parsing gtk-icon-sizes string: ' '

Question

Sorry I am pretty new to Linux machine, Ubuntu and Command line.

Here is what I did:

1. I tried to install PhpStorm 2016.3.2 on Linux machine (Ubuntu) by downloading the .gz file from JetBrains site.
2. I extracted the PhpStorm-2016.3.2.tar.gz file inside /home/[USERNAME]/apps/phpstorm/ folder.
3. I went inside bin/ folder and typed command line ./phpstorm.sh using Terminal.
4. It opens the PhpStorm application, but..

Error message:

It shows the following message while opening the app:

Error parsing gtk-icon-sizes string: ' '

Problem:

1. Application cannot stay open unless this Terminal stays open.
2. PhpStorm's icon is not created on my machine, so every time if I want to open PhpStorm, I have to open Terminal and type ./phpstorm.sh.

Questions:

1. While I was looking for solution, I got a feedback that I need to edit .bashrc file to make it executable in that path. What does it mean?
2. Do I have to modify the path inside "jediterm-bash.in"–> function load_interactive_configs?

bashrc