HTML Email Attachment Preview Firefox

HTML Email Attachment Preview

Preview HTML email attachments inline — no download required. With a per-sender whitelist.
xHeader
Modify request and response headers. No ads, no malware.

Features & Capabilities

Bank statements, credit card bills, insurance documents, government notices, tax invoices — a surprising share of email attachments arrive not as PDF, but as HTML. Click one in your inbox: PDFs and images get an inline preview with a built-in print button, but HTML attachments force you to download them and open from your PC.

· Just to read it: download → open the folder → double-click → go back to the folder and delete · To print or save as PDF: download → open → print → delete the downloaded file

A single statement, a single receipt — and you go through these steps every time.

HTML Email Attachment Preview solves this. HTML attachments open inline in your mailbox just like PDFs do, and you can print or save as PDF right from the preview. No downloads, no folder cleanup.

■ What it does

📄 Inline HTML attachment preview Renders HTML attachments directly inside your mailbox — no download, no temporary files. One click and the content is on screen.

🔐 Compatible with Korean security mail Automatically handles password-protected HTML emails commonly used by Korean banks and card issuers, so they render correctly inside the preview.

🛡 Sandboxed isolation Every attachment renders inside a sandboxed extension page with an opaque origin. HTML scripts inside cannot read your mail page, send authenticated requests, or reach extension APIs.

✅ Per-sender allowlist The first time you receive an HTML attachment from a sender, a non-blocking banner asks: "Render once / Always trust this sender / Dismiss." Trusted senders open instantly from then on.

⚡ Auto-allow mode For users already familiar with the senders they receive HTML statements from, the popup offers an "Auto-render all HTML attachments" toggle. Skip the per-sender confirmation entirely.

🖨 Print or save as PDF in one click A print button on the preview window lets you print to paper or save as PDF immediately. The download → open → print → delete cycle becomes a single click — especially useful for filing statements and saving receipts.

■ Supported mail services

· Gmail · Naver Mail · Daum Mail · Kakao Mail

■ Who it's for

· Anyone who receives bank or credit card statements as HTML attachments every month · People who get insurance policies or brokerage certificates as HTML · Recipients of government and public-institution notices delivered as HTML · Sole proprietors and freelancers who get tax invoices from clients as HTML · Anyone tired of the download → open → delete dance · Anyone who wants to keep their Downloads folder clean

■ Privacy

This extension does not transmit your data anywhere.

· No analytics, no tracking, no remote servers · Your trusted-senders list is stored only in your browser's sync storage · HTML attachments are rendered only inside a sandboxed page on your own machine — no content is sent outside · The attachment download itself uses the normal API of the mail service you're already logged into

■ How to use

After installing, just open a message with an HTML attachment in Gmail / Naver Mail / Daum Mail / Kakao Mail. No setup, no login required.

For senders you haven't approved yet, a one-time confirmation banner appears. Choose "Always trust this sender" and future attachments from them open automatically.

User Growth & Download Statistics

Manifest V3 Add-on
By:
박정섭
Daily users:
-
Version:
0.1.0 Last updated: 2026-07-27
Version code:
6372395
Creation date:
2026-07-24
Risk:
High risk impact High risk likelihood
Permissions:
Host permissions:
  • https://mail.google.com/*
  • https://mail.naver.com/*
  • https://download.mail.naver.com/*
  • https://mail.daum.net/*
  • https://cmail.daum.net/*
  • https://mail.kakao.com/*
  • https://cmail.kakao.com/*
Content scripts matches:
  • mail.google.com
  • mail.naver.com
  • mail.daum.net
  • mail.kakao.com
Size:
98.94KB
Email:
pa*****@parkjeongseop.com
URLs:
Website ,Privacy policy
Full description:
See detailed description
Source:
Firefox Add-ons Store
Data ingested on:
2026-08-02
Compare stats and ranking:

Contact the developer

Chrome-Stats does not own this Firefox add-on. Please use these information below to contact the Firefox add-on developer.
Developed by:
박정섭
Firefox Add-ons Store
https://addons.mozilla.org/firefox/addon/html-email-attachment-preview/
Email:
pa*****@parkjeongseop.com
Website:
https://github.com/ParkJeongseop/HTML-Email-Attachment-Preview

Is HTML Email Attachment Preview Safe?

Risk impact
Risk impact measures the level of extra permissions an extension has access to. A low risk impact extension cannot do much harms, whereas a high risk impact extension can do a lot of damage like stealing your password, bypassing your security settings, and accessing your personal data. High risk impact extensions are not necessarily malicious. However, if they do turn malicious, they can be very harmful.

HTML Email Attachment Preview requires some sensitive permissions that could impact your browser and data security. Exercise caution before installing.

Risk impact analysis details
  • Critical Request access to the following domains: google.com, naver.com, daum.net, kakao.com
  • High ******* ******* **** *** ****** ***** *** ***** ** ******* **** ********* ********* ** * *********** *****
Risk likelihood
Risk likelihood measures the probability that a Firefox add-on may turn malicious. This is determined by the publisher and the Firefox add-on reputation on Firefox Add-ons Store, the amount of time the Firefox add-on has been around, and other signals about the Firefox add-on. Our algorithms are not perfect, and are subject to change as we discover new ways to detect malicious extensions. We recommend that you always exercise caution when installing a Firefox add-on.

HTML Email Attachment Preview is recently added, and hasn't been around long enough for us to gather enough data to accurately assess its risk level.

Risk likelihood analysis details
  • High This extension was recently updated in the past month. New updates may not be stable or safe.
  • High **** ********* *** ******** ****** *** ********** *** *** ** ****** ** *****
  • High **** ********* *** *** **** ****** ********* ********** *** *** ** ****** ** *****
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