Headerline icon

Headerline

by Emory Barlow · Developer Tools
Manifest V3 Free
View in Chrome Web Store Data as of 16 Oct 2026

Inject custom HTTP request headers for development and testing

Users
20
−2 in 30 days
Rating
5.0 / 5
unchanged in 30 days
Ratings
4
0 in 30 days
Store rank
#150K
#125K among extensions
Version
1.0
updated 10 Jul 2026

Users

monthly, 3 months
01020Jul 2026Sep 2026Oct 2026
Latest, 16 Oct 2026: 20 usersMove the mouse over the chart for any month

Ratings count

monthly, 3 months
024Jul 2026Sep 2026Oct 2026
Latest, 16 Oct 2026: 4 ratingsMove the mouse over the chart for any month

The Chrome Web Store rounds user counts down to the leading digit, so the user line moves in steps. The ratings count is exact and is the better signal of real adoption.

About Headerline

Lightweight Chrome extension for injecting custom HTTP request headers. Supports up to 5 independent headers, each with its own on/off toggle. Built as a minimal, ad-free alternative to ModHeader for local development and blue/green testing.

Growth

WindowUsersChangeRatingsRating
7 days0+0.0%00.00
30 days−2−9.1%00.00

Version history

1 versions recorded
1.010 Jul 2026

Details

Category
Developer Tools
First seen
10 Jul 2026
Size
7 KB
Languages
en
Pricing
Free
Privacy policy
github.com
Extension ID
ljnkkcjbkkaaabbbkjfajlljkemfkgak

Permissions and risk

Moderate riskimpact 2, likelihood 2
Permissions
declarativeNetRequestWithHostAccessstorage
Site access
<all_urls>
Can read and change data on every website you visit.

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