Custom CSS by Denis

Minimal and secure way to add custom CSS per-domain

Custom CSS by Denis - Chrome Extension for Per-domain CSS styling

'Custom CSS by Denis' is a browser extension allowing users to add custom CSS styles on websites they visit. The extension is dedicated to maintaining security and requires domain-specific permissions. Unlike other similar extensions, it does not access all data on all websites. The permission is prompted and given only when a user edits CSS on a specific domain and if left unused, these permissions get dropped. The extension maintains an uncluttered and minimal UI with an editable area for CSS code for each specific domain.
Install from Chrome Web Store

Extension stats

Manifest V3
Rating: 4.49
(51)
Version: 1.3.5 (Last updated: 2025-01-03)
Creation date: 2018-10-20
Permissions:
  • activeTab
  • scripting
  • storage
Size: 165.89K
URLs: Website
Full description: See detailed description

Other platforms

Not available on Android
Not available on Firefox
Not available on Edge

User reviews

These summaries are automatically generated weekly using AI based on recent user reviews. Chrome Web Store does not verify user reviews, so some user reviews may be inaccurate, spammy, or outdated.
Pros
  • Simple and easy to use
  • Works perfectly without any fuss
  • Open source with no login/account requirements
  • Indispensable for small UI tweaks
  • Good for enhancing usability and accessibility of websites
Cons
  • Styles often get overridden by existing website styles
  • Character limit for CSS edits creates issues
  • No option for syntax highlighting or IDE features
  • Styles do not apply to iframes
  • Some users report recent issues with changes getting overwritten
Most mentioned
  • Works like a charm
  • Simplicity and effectiveness
  • Need for improved features like URL portion styling
  • Issues with styles not applying due to character limits
  • Desire for more control over CSS application and order
User reviews
Exactly what I was looking for! This is a lifesaver as a CS major.
by Jac Chambers, 2025-02-12

Great extension. Been using for months and have had no issues. Simple and does what you expect. Thanks. One request: possible to get the styles to be applied to an iframe of the same domain? Currently the styles only get applied to the parent window. Using a Javascript extension similar to this one to inject the styles into the iframe.
by Ryan Hanson, 2025-02-07

Exactly what an extension like this should be. Simple, local, open source, and works perfectly with no fuss and no login/account or "pro" version needed.
by Jeff Yen, 2024-12-10
View all user reviews

Extension safety

Risk impact

Custom CSS by Denis does not require any sensitive permissions.

Risk impact analysis details
  • Low Request access to the following domains:
Risk likelihood

We don't have sufficient data to confidently determine the risk likelihood of Custom CSS by Denis. Use it at your own risk.

Risk likelihood analysis details
  • High This extension has low user count. Unpopular extensions may not be stable or safe.
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  • Low **** ********* *** ***** **** **** * ****** **** ***** ********** *** **** ****** ** ** ****** *** *****
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