Twenty Seventeen is the official WordPress theme in 2017 and it’s really awesome, but unfortunately it has no way to display a sidebar on pages 🙁
Let’s fix that.
This tiny plugin will add the default sidebar to all the pages, including the front page! You don’t have to touch a single line of code, and it works for Twenty Seventeen child themes too.
For best results, go to Customize > Theme Options and set Page Layout to One Column.
If you want your page sidebar to differ from your post sidebar, it is recommended to also install Content Aware Sidebars in addition to this plugin. That will allow you to show and hide widget areas on a wide range of conditions, giving you complete control over your sidebar.