SXA toolbox missing when editing pages and partial designs

Question

Somewhere between upgrading Sitecore/SXA and merging conflicts with the themes, all of a sudden the toolbox does not appear.

What should I verify to get it working again?

Answer 1

After working with Adam N. and him pointing me in the right direction I discovered a few things.

1. Confirm that the Drag and Drop settings is enabled while in the Experience Editor.

2. Confirm that the Editing Theme in your site's theme has the BaseLayout themes added and in the right order.

3. Take notice that the first Base Theme in the list is for Editing Theme. This is an SXA theme that includes the toolbox.js required to show the theme.

Now the beautiful toolbox appears!