Why is extended partition option is grayed out in GParted?

I’m trying to dual boot Lubuntu with macOS Sierra.

I boot using a USB flash drive, select “Try without installing”, and when I launch GParted, see about 50GB unallocated space.

However, GParted extended partition option is grayed out.

I’m not a Linux admin by any means, not even close, so not sure what’s going on here.
See screenshot here

Asked By: Abhijit Sarkar

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This is a GPT disk. There are no extended partitions on GPT.
You can create almost unlimited number of primary partitions.

So create as many primary partitions as you need.

Answered By: Pilot6