Download CSS Debug Overlay Plus

Name: CSS Debug Overlay Plus
Author: Francis Ruiz

By: Francis Ruiz

Download CSS Debug Overlay Plus (current and past versions) for Firefox

Latest Version: 1.3 Updated: 9 months ago

Ready to install?

CSS Debug Overlay Plus is available to install from Firefox Add-ons Store and for download from this page.

View source code

Available versions

You can find the current and older versions of CSS Debug Overlay Plus here. You can download the archived versions or inspect their source codes.

As a free user, you can download up to 3 latest versions.

Upgrade to download older versions

Version	Download	Size	Download count	Timestamp
1.3	XPI · ZIP · Source code	15.50KB	0	2025-10-09

2025-10-09 · 0 downloads

XPI ZIP Source code

Install XPI file

An XPI file, short for "XPInstall," is a compressed file format used primarily by Mozilla applications, like Firefox and Thunderbird, to distribute and install add-ons or extensions. These files are similar in function to CRX files for Chrome but cater to the Mozilla ecosystem.

Simply drag-and-drop the XPI into Firefox to install the add-on.

Install ZIP file

Download the CSS Debug Overlay Plus ZIP file.
In Firefox browser, go to about:addons to open Add-ons Manager
Click on ⚙, Install Add-on From File
Select the CSS Debug Overlay Plus ZIP file from step 1. CSS Debug Overlay Plus is now installed on your browser.