I get the following error when I attempt to install flarum/embed. What am I doing wrong?
mark@forum:~$ composer require "flarum/embed":"dev-master"
./composer.json has been created
Loading composer repositories with package information
Updating dependencies (including require-dev)
Your requirements could not be resolved to an installable set of packages.
- Installation request for flarum/embed dev-master -> satisfiable by flarum/embed[dev-master].
- flarum/embed dev-master requires flarum/core 0.1.0-beta.13 -> satisfiable by flarum/core[0.1.x-dev, v0.1.0-beta.13] but these conflict with your requirements or minimum-stability.
Installation failed, deleting ./composer.json.