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Ensure that PHPStorm is listening to debug connections, check the status line at the bottom: 

Problems with IPv6

In my case PHPStorm was listening by default on IPv6 interface:

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But the docker containers are only talking IPv4. The easiest way was to disable IPv6 in PHPStorm, which I was able to do by adding / editing the file phpstorm64.vmoptions in the root of my home directory and adding there the line:

-Djava.net.preferIPv4Stack=true

How to find the config file:

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Check https://www.jetbrains.com/help/phpstorm/tuning-the-ide.html how to find the right config file!

Now netstat looks better:

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Browser

Install helper

• Install XDebug helper extension for your browser

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