Networking in WebStorm
WebStorm requires Internet connection for a wide variety of tasks. For example:
Checking for WebStorm updates
Code inspections that can verify external resources
Communication with the version control servers, task servers
Anonymous usage statistics
Working with remote Node.js interpreters
Besides that, WebStorm provides IPC for commands (for example, open files), and the built-in Web server.
Some of the communication requirements are configurable:
To turn off checking for updates, open the Settings | Updates page, and clear the Check for updates in channel checkbox.
To disable code inspection that highlights dead links, open the Settings | Inspections page, and clear the checkbox to the left of the HTML inspection Non-existent web resources.
You can control the frequency of sending usage statistics, or even completely disable this function in the page Settings | Usage statistics.