Latest Version:
25.4 Updated:
10 months ago
Ready to install?
HeaderMod is available to install from Firefox Add-ons Store and for download from this page.
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Total downloads
Available versions
You can find the current and older versions of HeaderMod 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 |
|---|---|---|---|---|
| 25.4 | XPI · ZIP · Source code | 20.55KB | 0 | 2025-08-09 |
| 25.3 | XPI · ZIP · Source code | 21.91KB | 0 | 2025-07-17 |
25.4 20.55KB
25.3 21.91KB
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 HeaderMod ZIP file.
- In Firefox browser, go to
about:addonsto open Add-ons Manager - Click on ⚙, Install Add-on From File

- Select the HeaderMod ZIP file from step 1. HeaderMod is now installed on your browser.
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