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diff --git a/packages/gitbook-core/src/components/InjectedComponent.js b/packages/gitbook-core/src/components/InjectedComponent.js
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+const React = require('react');
+const ReactRedux = require('react-redux');
+const { List } = require('immutable');
+
+const { findMatchingComponents } = require('../actions/components');
+
+/*
+    Public: InjectedComponent makes it easy to include a set of dynamically registered
+    components inside of your React render method. Rather than explicitly render
+    an array of buttons, for example, you can use InjectedComponentSet:
+
+    ```js
+    <InjectedComponentSet className="message-actions"
+                      matching={{role: 'ThreadActionButton'}}
+                      props={{ a: 1 }}>
+    ```
+
+    InjectedComponentSet will look up components registered for the location you provide,
+    render them inside a {Flexbox} and pass them `exposedProps`. By default, all injected
+    children are rendered inside {UnsafeComponent} wrappers to prevent third-party code
+    from throwing exceptions that break React renders.
+
+    InjectedComponentSet monitors the ComponentStore for changes. If a new component
+    is registered into the location you provide, InjectedComponentSet will re-render.
+    If no matching components is found, the InjectedComponent renders an empty span.
+ */
+
+const Injection = React.createClass({
+    propTypes: {
+        component: React.PropTypes.func,
+        props:     React.PropTypes.object,
+        children:  React.PropTypes.node
+    },
+
+    render() {
+        const Comp = this.props.component;
+        const { props, children } = this.props;
+
+        // TODO: try to render with an error handling for unsafe component
+        return <Comp {...props}>{children}</Comp>;
+    }
+});
+
+const InjectedComponentSet = React.createClass({
+    propTypes: {
+        components: React.PropTypes.oneOfType([
+            React.PropTypes.arrayOf(React.PropTypes.func),
+            React.PropTypes.instanceOf(List)
+        ]).isRequired,
+        props:    React.PropTypes.object,
+        children: React.PropTypes.node
+    },
+
+    render() {
+        const { components, props, children, ...divProps } = this.props;
+
+        const inner = components.map((Comp, i) => <Injection key={i} component={Comp} props={props} />);
+
+        return (
+            <div {...divProps}>
+                {children}
+                {inner}
+            </div>
+        );
+    }
+});
+
+/**
+ * Render only the first component matching
+ */
+const InjectedComponent = React.createClass({
+    propTypes: {
+        components:    React.PropTypes.oneOfType([
+            React.PropTypes.arrayOf(React.PropTypes.func),
+            React.PropTypes.instanceOf(List)
+        ]).isRequired,
+        props:    React.PropTypes.object,
+        children: React.PropTypes.node
+    },
+
+    render() {
+        let { components, props, children } = this.props;
+
+        if (!children) {
+            children = null;
+        } else {
+            children = React.Children.only(children);
+        }
+
+        return components.reduce((inner, Comp) => {
+            return (
+                <Injection component={Comp} props={props}>
+                    {inner}
+                </Injection>
+            );
+        }, children);
+    }
+});
+
+/**
+ * Map Redux state to InjectedComponentSet's props
+ */
+function mapStateToProps(state, props) {
+    const { components } = state;
+    const { matching } = props;
+
+    return {
+        components: findMatchingComponents(components, matching)
+    };
+}
+
+const connect = ReactRedux.connect(mapStateToProps);
+
+module.exports = {
+    InjectedComponent:    connect(InjectedComponent),
+    InjectedComponentSet: connect(InjectedComponentSet)
+};