Reviews of CustomCSS Injector

By: Blizz3 Add-on

List of user reviews and ratings for CustomCSS Injector

Total ratings

4.27 (Rating count: 22)

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Review summary

Overall, reviewers find CustomCSS Injector powerful, easy to use, and lightweight with strong multi-scope CSS override capabilities, and effective for practical page tweaks. However, reliability issues with domain-level CSS, the need to save changes before leaving the editor, late injection timing, occasional bugs, and requests for export/import/list features temper enthusiasm. The add-on is valuable but could use stability and UX improvements.

Pros

Powerful and easy to use for CSS overrides across sites.
Lightweight and unobtrusive.
Editor supports syntax highlighting.
Works across multiple scope levels (Global, URL, Domain).
Practical usefulness for fixing problematic pages and customizing experiences (overriding CSS on tricky sites).

Cons

Reliability issues with domain-level CSS: sometimes not applied, requires refresh, or can mix across domains.
Unsaved changes can be lost if you don't click Save before leaving the editor.
CSS injection can occur after the page has loaded, limiting early rendering changes.
Occasional bugs or lack of feedback (initially shows errors or red highlight).
Missing export/import or domain/list view feature for managing multiple CSS rules.

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User Reviews

Recent rating average: 4.10

All time rating average: 4.27

Upgrade to see all 22 reviews

5% (1)

Date	Author	Comment
2026-03-31	*****	Save button doesn't work for me.
Save button doesn't work for me.
2026-02-20	Pi*****

2026-01-02	Mo*****	Very good, but it would be nice if there was a way to see a list of the domains/URLs we have custom CSS for, as well as being able to export/import.
Very good, but it would be nice if there was a way to see a list of the domains/URLs we have custom CSS for, as well as being able to export/import.
2025-09-20	Na*****	Pros: - Syntax highlighting in the editor - Works on 3 levels: Globally, URL, and Domain - Very lightweight. You won't even notice it's there! Cons: - It's really frustrating that I need to click "Save" before I click out of the editor or I lose my changes. While working on some CSS for Discord's Streamkit Overlay, I lost a ton of changes by accidentally clicking outside of the editor. - Sometimes, the domain level CSS does not get applied or doesn't come up when you open the extension. I've had to refresh up to 5 times to get it to appear and no amount of closing and reopening the extension will fix it. - For some reason, it keeps mixing up some of my domain-level CSS changes. Sometimes I'll have my custom CSS for a website where I study language applied to YouTube and vice versa for example. Overall, it's a very useful extension that I find incredibly helpful for helping me study by adding things spoiler effects to flash cards and such.
Pros: - Syntax highlighting in the editor - Works on 3 levels: Globally, URL, and Domain - Very lightweight. You won't even notice it's there! Cons: - It's really frustrating that I need to click "Save" before I click out of the editor or I lose my changes. While working on some CSS for Discord's Streamkit Overlay, I lost a ton of changes by accidentally clicking outside of the editor. - Sometimes, the domain level CSS does not get applied or doesn't come up when you open the extension. I've had to refresh up to 5 times to get it to appear and no amount of closing and reopening the extension will fix it. - For some reason, it keeps mixing up some of my domain-level CSS changes. Sometimes I'll have my custom CSS for a website where I study language applied to YouTube and vice versa for example. Overall, it's a very useful extension that I find incredibly helpful for helping me study by adding things spoiler effects to flash cards and such.
2025-06-29	ly*****

2024-11-19	Fi*****	Fonction mais comment ajouter pour differents site ?
Fonction mais comment ajouter pour differents site ?
2022-05-10	Fi*****

2022-04-03	Si*****

2022-03-13	Vi*****

2021-08-21	Ga*****	Works Great!
Works Great!