The Expanded Sidebar is back in Shift Ultra! Currently, the feature is available on the Beta V9.1.3 version only. If you want to access it early, please download Shift Beta from here. Simply click on "Beta" for the download to start.
After installing Shift Beta, you can right-click on your sidebar and select "Expanded" to expand the sidebar. Additionally, you can do it from the settings panel by going to Quick Settings (upper right corner) > scrolling down to "Sidebar size" and choosing the "Expanded" option.
Learn about more options for customizing the sidebar here.