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Preview of Customizer

Customizer by Robustus

Add custom CSS to one or many sites

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Customizer: Custom CSS for the Web
About this extension
Sometimes websites don't look the way you want them to. Simplify or change them with Cascading Style Sheets. CSS can be applied to many pages with the * wildcard. It is applied before the HTML loads. The CSS is edited in a popup window or the big options page, not in a sidebar of the page; you are not hindered by the page.

Features:
• Edit CSS: View & edit styling for one page or many
• Storage Sync: Options saved for use on any computer

Instructions: Configure Keyboard Shortcut:
1. Click the icon for this extension
2. Click "Keyboard shortcuts"
3. Make a keyboard shortcut for "Big options page: edit site"
4. In the future, use this shortcut so you can use "Inspect Element"

Instructions: Add Site:
1. Open the popup or big options page
2. Go to the field "Add site"
3. Type in a URL like the following
• Normal: en.wikipedia.org
• Wildcard: *.wikipedia.org or *
4. Hit enter or click the plus button

Instructions: Edit CSS
1. Open the popup or big options page
2. Add rules and change properties
3. Refresh the site
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Permissions and data

Required permissions:

  • Access browser tabs
  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
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Version
4.0
Size
174.32 KB
Last updated
a month ago (May 21, 2026)
Related Categories
  • Web Development
  • Appearance
License
GNU General Public License v3.0 only
Version History
  • See all versions
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