Exception: Can't initialize ccache use: Read-only file system

[Akselmo]

Checklist

• [x] I agree to follow the Code of Conduct that this project adheres to.
• [x] I have searched the issue tracker for a bug that matches the one I want to file, without success.

flatpak-builder version

1.4.4

Flatpak version

1.16.1

How to reproduce

1. Run flatpak run --command=flathub-build org.flatpak.Builder --install manifestname.json

Expected Behavior

It would build and do it's thing as expected.

Actual Behavior

I get following message in terminal

❯ flatpak run --command=flathub-build org.flatpak.Builder --install org.kde.komodo.json
Running: flatpak-builder --verbose --force-clean --sandbox --keep-build-dirs --override-source-date-epoch 1321009871 --user --install-deps-from=flathub --ccache --mirror-screenshots-url=https://dl.flathub.org/media --repo=repo builddir --install org.kde.komodo.json
FB: Running: git config --get user.email
FB: Running: git config --get user.name
Can't initialize ccache use: Read-only file system

Tested with various manifest files, always same end result: Can't initialize ccache use: Read-only file system

Additional Information

No response