Appearance
Themes, light and dark, and file icons.
Themes
By default, Reviewer draws on your terminal's own background and uses its colours, so it fits whatever theme your terminal has. Code is highlighted with Reviewer's light or dark colours, to match.
Press ⌘, (or ⌃T) to open the theme picker. Each theme previews as you move through the list. Press Tab to switch between System, Light and Dark.
As in the Mac app, you choose one theme for light and one for dark. With System, Reviewer follows your computer's appearance as it changes.
To try a theme for one run only:
reviewer --theme terminal
reviewer --lightFile icons
Files show icons by type in the tree, tabs, diff and palette. They need a Nerd Font in your terminal. To turn them off, choose show / hide file icons in the command palette.