Reviews of Modify Header Value

By: Milen Add-on

List of user reviews and ratings for Modify Header Value

Total ratings

3.62 (Rating count: 66)

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Review summary

Summary: Users generally value the core ability to add and tweak HTTP headers in the browser and view it as a useful tool, sometimes as a strong alternative to similar extensions. However, many reviews note reliability problems (headers may not be applied or only affect the first request), a confusing UI, breakage after updates (including MV3 changes), and that it doesn’t affect client-side XHR/fetch requests. Some sites can break when altering headers (e.g., YouTube). Overall, it’s helpful when working, but stability and scope issues limit its consistency.

Pros

Core feature: enables adding and adjusting HTTP header values in browser requests.
Useful for testing and security scenarios; described as very useful by a security researcher.
Provides a good alternative to similar extensions (e.g., Requestly).
Gives flexibility to tweak any header you desire.

Cons

Unreliable header changes: changes may not apply consistently and often affect only the first request.
Update-induced breakage: updates can break the add-on or limit its functionality (e.g., MV3 changes).
UI/UX unclear: enable/disable state isn't clearly indicated.
Does not affect client-side XHR/fetch requests.
Can cause site breakages (e.g., YouTube) when modifying certain headers.

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User Reviews

Recent rating average: 2.00

All time rating average: 3.62

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14% (10)

Date	Author	Comment
2026-04-13	S.*****	Not working
Not working
2026-03-18	No*****	Can't change existing header after adding it. Even when you add a new header, it is not reliably added. I wish the old ModHeader extension was still available.
Can't change existing header after adding it. Even when you add a new header, it is not reliably added. I wish the old ModHeader extension was still available.
2025-08-10	Fi*****

2025-06-12	Ne*****	It no longer works
It no longer works
2025-05-23	Sa*****	It works, but the UI for enabling it very badly designed. The UI element just toggles between blue and white, with no indication which ones is on and which one is off.
It works, but the UI for enabling it very badly designed. The UI element just toggles between blue and white, with no indication which ones is on and which one is off.
2025-05-21	gl*****	This does not add the header to client-side xhr requests, that is, fetches from the browser.
This does not add the header to client-side xhr requests, that is, fetches from the browser.
2025-04-29	ro*****	got broken after Apr. 15 update
got broken after Apr. 15 update
2025-04-28	Zh*****	Update for manifest V3 broke the add-on ? It only works for the homepage now or at least, only for the first request maybe.
Update for manifest V3 broke the add-on ? It only works for the homepage now or at least, only for the first request maybe.
2025-04-12	Ri*****	Works only for first request to page???
Works only for first request to page???
2025-04-07	远离*****