Below details are required to be added to Atlassian Companion App Documentation page. Please review and help us update it ASAP.

Companion app configuration file:

• For the .exe, C:\Users\username\AppData\Local\atlassian-desktop-companion/app-version/resources/companionConfig.json
• For the .msi, C:\Program Files (x86)\Atlassian Companion/resources/companionConfig.json
• For the .dmg, /Applications/Atlassian Companion.app/Contents/Resources/companionConfig.json

Disable "About"/"Welcome" dialog

This configuration is available from Companion App version 1.3.0 introduced by [CONFSERVER-60433 - Atlassian Companion app prompt should not appear
to all users during first startup Citrix desktops|https://jira.atlassian.com/browse/CONFSERVER-60433]
Use "showWelcomeDialog":"true" option in companionConfig.json to disable the introductory "About"/"Welcome" dialog from appearing on the first launch of Companion.

Disable launching of the websocket server.

The launching of the websocket server can be disabled by modifying the companionConfig.json file in the install directory and setting "websocketsEnabled":"false".
This configuration option was introduced with Companion should have an option to disable running local websocket server from Companion App version 1.3.0.

Enable Companion app Debug logs:

Change the "logLevel":"info" to "logLevel":"debug" in the companionConfig.json file to enable Debug logs for Companion App.

Related Knowledge articles:

https://confluence.atlassian.com/display/CONFKB/Locating+the+Companion+App+Log+File
https://confluence.atlassian.com/confkb/how-to-change-the-file-types-blocked-by-companion-in-windows-987144838.html