Manual Partitioning During Ubuntu Install – Remaining Free Space ‘Unusable’

Q: Manual Partitioning During Ubuntu Install – Remaining Free Space Unusable
A: Disk formatted with MBR allows only 4 partitions, thus the space left is marked unusable.

Source: https://askubuntu.com/questions/1145369/how-to-install-ubuntu-if-the-free-space-appears-as-unusable#comment1900955_1145369

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