Introducing Cascadea, the first custom style manager designed as a native Mac application and Safari App Extension. Cascadea makes it easy to install custom styles that change the look and feel of any website you want. Whether you want your social media feed to burst with color, or to give your eyes a break with a darker style, Cascadea gives you the freedom to paint the web in your colors.

Installing styles is easy - you can easily import styles from popular custom style websites, or import any CSS file from a URL or local file. Once installed, Cascadea has a clean, simple user interface for quickly toggling or deleting styles. Since Cascadea is built with a fast, fluid native UI, it's easy to mass-toggle or mass-delete styles, drag them around to organize your style list, or export and import entire databases of styles.

Cascadea is also an incredibly powerful tool for CSS developers, whether you're writing custom styles of your own or using it as part of your web development workflow. Cascadea includes a fully-featured code editor for writing custom stylesheets, with support for autocompletion, syntax highlighting, automatic indentation, code folding, beautification, multicursor support, and more. Choose between multiple color themes for the editor, open multiple styles in tabs, and watch Safari update live when you save changes. Plus, if you prefer your own code editor, you can easily export and import a standard CSS file into and out of Cascadea.

Other features include:
• The fastest, cleanest UI of any custom style manager.
• Full support for Dark Mode in macOS Mojave.
• Touch Bar support on equipped MacBook Pro models.
• Automatically update styles imported from a URL.
• Easily duplicate imported styles to edit a local copy without it being overwritten by an update.
• Basic support for the UserCSS format, with deeper support coming soon.
• Change the injection order of styles by just dragging and dropping entries in your style list.
• Export your entire style collection to a single database file, and import them back just as easily.
• Open Cascadea quickly or toggle your styles with a click of a button in your Safari toolbar.
• No user tracking. At all. Ever. Cascadea collects absolutely no data from you, outside of opt-in anonymized crash reports provided by Apple through the App Store.

What's New

Version 1.1.1

• Fixed an issue that could cause the Safari extension to crash when viewing Safari’s New Tab page.

Ratings and Reviews

5.0 out of 5
6 Ratings
6 Ratings
Momen Abdelkarim

Didn't expect it to be this good

This kind of functionality is something I would only expect on Chrome or maybe Firefox, but seeing this on Safari is amazing. It can even import Stylish themes, which means you have the best repository available to use immediately.

But there are some downsides and problems I've ran into:
1) Some websites seem to freeze up completely if I have a Cascadea theme on them and won't work until I disable the theme. I'm not sure if this is from Cascadea or the theme, but this freezing up doesn't occur via Chrome on Stylish.
2) The fact that the Cascadea app has to be running in the background the whole time, minimized in my dock, is kind of annoying as I like to keep my dock minimal. Being a Safari extension you think it would just work without the application in the dock but it doesn't (at least from my understanding).

This app is brand new, so I hope the developer might be able to dress the above two concerns in the near future. But to be clear, it is an amazing app regardless, hence the 5-star!

Developer Response

I'm glad to hear you're enjoying Cascadea! If you're having any trouble with certain themes causing websites to freeze, please send me an email at with info on what websites and styles seem to cause the issue. I'd be happy to look into that with you.

As far as point #2, you don't need to keep the Cascadea app running in the background. As long as you keep the extension enabled in Safari, your styles will continue to be applied.

Thanks for using Cascadea!
- Mike


Simply fantastic

Ever since the privacy issues with Stylish I've been looking for a replacement for Safari and haven't been able to find one (Freestyler also tracks). Until now.

It's awesome. Supports user styles, auto updating, and even adds some extra features.



Someone did it! What an absolute mad lad! I can finally use userstyles in Safari 12! God bless you


Mike Freuden
15.7 MB
macOS 10.13 or later, 64-bit processor
Age Rating
Rated 4+
© 2018 Michael Freuden.


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