Why images stay off until you click
October 12, 2026 · 2 min read
Open an email here and you may see a bar that says remote images are hidden, with a button to show them. That is on purpose, and the reason fits in a single pixel.
What a tracking pixel is
A tracking pixel is a tiny image, often 1×1 pixel and transparent, placed inside an HTML email. The image lives on the sender's server, and its web address usually contains an ID unique to you. When your mail reader loads images, it requests that address, and the sender's server writes down:
- that this exact message was opened;
- when it was opened, and how many times;
- the IP address that asked, which hints at your rough location and network;
- details about the app or browser you used.
Why it matters for a throwaway address
The biggest leak is simple: an open tells the sender the address is alive. Addresses known to be read are worth more to spammers than ones that bounce or sit unread. Blocking images by default keeps that signal from leaving.
What the reader here does
- Remote images are off until you press "Show images". Small images written directly into the message code can still display, because loading them contacts no one.
- Scripts never run. The message is shown in a locked-down frame with scripts disabled.
- Links open in a new tab and do not pass along which page you came from.
When to press "Show images"
If the message is from a site you just signed up to and the layout looks broken without its pictures, showing images is usually harmless. The site already knows you signed up a moment ago. For mail from senders you do not recognise, leave them off. Most text-based codes and links work fine without images.