luceos Your requirements could not be resolved to an installable set of packages.
- Root composer.json requires selfmade/flarum-ext-ninja *@dev -> satisfiable by selfmade/flarum-ext-ninja[dev-master].
- selfmade/flarum-ext-ninja dev-master requires flarum/core 0.1.0-beta.8 -> found flarum/core[v0.1.0-beta.8, ..., v0.1.0-beta.16] but it conflicts with your root composer.json require (1.0).
Use the option --with-all-dependencies (-W) to allow upgrades, downgrades and removals for packages currently locked to specific versions.
Installation failed, reverting ./composer.json and ./composer.lock to their original content.
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