Notes/src/public/app/widgets/containers/right_pane_container.js

import FlexContainer from "./flex_container.js";

export default class RightPaneContainer extends FlexContainer {
    constructor() {
        super('column');

        this.id('right-pane');
        this.css('height', '100%');
    }

    isEnabled() {
        return super.isEnabled() && this.children.length > 0 && !!this.children.find(ch => ch.isEnabled());
    }

    handleEventInChildren(name, data) {
        const promise = super.handleEventInChildren(name, data);

        if (['activeContextChanged', 'noteSwitchedAndActivated', 'noteSwitched'].includes(name)) {
            // right pane is displayed only if some child widget is active
            // we'll reevaluate the visibility based on events which are probable to cause visibility change
            // but these events needs to be finished and only then we check
            promise.then(() => this.toggleInt(this.isEnabled()));
        }

        return promise;
    }
}