Download LeetCode Classic

Name: LeetCode Classic
Author: Chandrakishor Singh

By: Chandrakishor Singh Add-on

Download LeetCode Classic (current and past versions) for Firefox

Latest Version: 1.1.1 Updated: 2 months ago

Ready to install?

LeetCode Classic 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 LeetCode Classic 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	Timestamp
1.1.1	XPI · ZIP · Source code	247.15KB	2026-05-21
1.0.1	XPI · ZIP · Source code	245.55KB	2026-05-10
1.0.0	XPI · ZIP · Source code	9.74KB	2026-05-06

2026-05-21 · 0 downloads

XPI ZIP Source code

2026-05-10 · 0 downloads

XPI ZIP Source code

2026-05-06 · 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 LeetCode Classic ZIP file.
In Firefox browser, go to about:addons to open Add-ons Manager
Click on ⚙, Install Add-on From File
Select the LeetCode Classic ZIP file from step 1. LeetCode Classic is now installed on your browser.