Feather Documentation
Native markdown editor for Windows
Themes & Customization
App Theme
Feather supports three app-wide theme modes:
- System default — follows your Windows light/dark setting
- Light
- Dark
On Windows 11, the app uses the Mica backdrop for a translucent material effect behind the window.
To change the app theme:
- Open Settings (gear icon or Ctrl+,)
- Go to Appearance
- Select your preferred theme
Preview Themes
The preview theme controls how your markdown renders in the preview pane. It is independent of the app theme.
Preview Theme Mode
Choose how the preview theme responds to light and dark:
- Follow app — matches the current app theme
- Always light — preview always uses the light variant
- Always dark — preview always uses the dark variant
Built-in Themes
Feather includes 9 preview themes:
| Theme | Description |
|---|---|
| Default | Clean, balanced styling |
| GitHub | Mimics GitHub's markdown rendering |
| Academic | Serif fonts with a scholarly feel |
| Newsletter | Editorial, magazine-style layout |
| Minimal | Stripped-down, distraction-free |
| Night Owl | Dark theme with warm colors |
| Catppuccin | Pastel dark theme |
| Windows 98 | Retro nostalgic look |
| Windows XP | Classic Windows styling |
Each theme includes matching colors for highlight marks (==text==) and Mermaid diagrams.
Custom CSS
You can replace the built-in preview stylesheet with your own CSS file.
- Open Settings > Preview
- Under Custom CSS, select your
.cssfile - The preview pane will immediately use your stylesheet
Your custom CSS controls all preview rendering: headings, paragraphs, code blocks, tables, blockquotes, and more. To revert to the built-in themes, remove the custom CSS file from settings.
Editor Font
- Open Settings > Editor to change the editing font
- A searchable font picker lists all installed system fonts
- Default font: Cascadia Code
- Monospace fonts are recommended for markdown editing
Preview Font
- Optionally override the default font used by the preview theme
- Set in Settings > Preview
- Uses the same system font picker as the editor font setting
Font Size
- Adjustable from 12pt to 24pt via a slider in Settings
- Applies to the editor pane
- Preview font size follows the selected preview theme