Questions[pycharm](ubuntu)

I wanted to install Pycharm Community edition using snap with the following command:

sudo snap install pycharm-community

Unfortunately, I got the following error message:

error: This revision of snap "pycharm-community" was published using classic confinement and thus may perform arbitrary system changes outside of the security sandbox that snaps are usually confined to, which may put your system at risk.
If you understand and want to proceed repeat the command including
--classic.

My question is: is it safe to proceed and install it using --classic as they suggest? What are the risks of doing so? (i.e what kind of "arbitrary system changes" can happen?) And lastly, has anyone tried it and did everything go well?

I previously installed IntelliJ IDEA a few weeks ago and didn't get this problem. Of course, there are certainly other ways to install it, but I found snap to be a convenient tool as then I just need to type the name of the program in the terminal to launch it.

I've downloaded pyCharm from jetbrains website. Then I've extracted that downloaded file and via terminal I ran this command to install pycharm,

./pycharm.sh

Is stopped with the mention Installation completed so I activated the pycharm. But later I searched on Applications but could not find pycharm. Why?

Is it not possible to install an older version of Pycharm community using snap?

I tried snap install pycharm-community=2018.2.5 but it does not work.

I installed Pycharm, which automatically created then a shortcut at the Applications Menu. But the shortcut does not work and shows the message

No JDK found. Please validate either PYCHARM_JDK, JDK_HOME or JAVA_HOME    environment variable points to valid JDK installation.

But Java is installed:

java version "1.8.0_73"
Java(TM) SE Runtime Environment (build 1.8.0_73-b02)
Java HotSpot(TM) 64-Bit Server VM (build 25.73-b02, mixed mode).

Besides, if I run the script "pycharm.sh" from the command line, it works.

Unlike the previous post, the tar.gz of PyCharm or SmartGit does not have make or ./configure.

I always open terminal at bin and type ./pycharm.sh, which leaves the terminal open while I'm using the application.

How can I just click the PyCharm application icon and run it without a terminal in Ubuntu Desktop?