Slack Columns is a free Chrome add-on developed by koheiyatsushiro. It falls under the category of Browsers and specifically the subcategory of Add-ons & Tools. With Slack Columns, users can display multiple channels side by side.

This add-on allows users to register the URLs of the channels they want to display. When viewing their Slack workspace, the registered channels will be shown side by side. Users can register channels from multiple workspaces as long as they are logged in to their browser.

Please note that Slack Columns is currently at version 1.0.2, with the latest updates including changes to the title and description of the options page.