Injected into Gmail
A pill-shaped Export button appears beside the subject heading, with a dropdown offering PDF
and image output. A MutationObserver re-injects it whenever Gmail swaps in another
conversation.
Mail Thread Export
Export the mail thread you are reading to a clean, single-page PDF or PNG — locally, with no network calls.
What it is
Section titled “What it is”Mail Thread Export is a Chrome extension (Manifest V3) that injects an Export button next to the
subject line of the Gmail conversation you have open. Choosing Export as PDF or Export as Image
clones the conversation DOM, removes the surrounding Gmail interface, rasterises the result with
html2canvas at 2x, and hands you a file.
Why not just print to PDF
Section titled “Why not just print to PDF”Gmail’s print view introduces page breaks, its own headers and footers, and a print stylesheet that frequently mangles the layout of rich HTML mail. This extension captures what is actually on screen instead, and writes it to a single continuous page sized to the content.
Features
Section titled “Features”One continuous page
The PDF page is sized to the rendered canvas, so long threads are never cut in half by a page break.
Interface stripped
Toolbars, reply/forward/more buttons, stars, labels, alerts and tooltip-bearing controls are removed from the clone. English and German Gmail labels are both recognised.
Stable 800 px layout
The clone renders at a fixed desktop width, so output does not depend on your window size.
CJK-safe font stack
The export forces a Japanese-capable font stack so CJK mail does not render as tofu boxes.
No network, no storage
No fetch calls, no analytics, no accounts, no storage permission. Everything happens in the
page.
What it does not do
Section titled “What it does not do”- The toolbar popup is non-functional — it messages a listener the content script never registers. Use the injected Export button. See Architecture.
- The PDF holds a raster image, so its text is not selectable or searchable.
- It targets Gmail’s web UI only; other webmail is not supported.
Next steps
Section titled “Next steps”Installation
Build from source and load unpacked — Installation.
Configuration
Every tunable value and where to change it — Configuration.