Looking up a MAC address by its first three bytes misses the holders of smaller IEEE blocks
A MAC address carries two flag bits and, for a factory address, the organisation that bought its block from the IEEE. In...
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How a Taiwan ID number is built, and what its check digit misses
A Taiwan ID number is a letter, a sex digit, a seven-digit serial and a check digit. Where the check-digit rule was prin...
What the 12 digits of a Malaysian IC number record
What each part of a MyKad number (nombor IC) records: the date of birth with no century, JPN's state and country codes i...
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Electronic signatures in Singapore and Malaysia, and the documents the law still excludes
In Singapore a typed, drawn or pasted signature can meet a legal signature requirement if the method identifies the sign...
Singapore's data protection law does not cover the government
The PDPA's data protection obligations do not bind ministries, departments or gazetted statutory boards, so the right to...
Two ASEAN countries cannot use Apple's Private Relay, and Thailand is still being sold it
Apple publishes an exact 160-country list for iCloud Private Relay. The Philippines and Thailand are absent while every...
The privacy header thousands of sites copied now guards something else
Permissions-Policy: interest-cohort=() was added in 2021 to opt out of FLoC. FLoC was cancelled, and Chromium repointed...
Singapore's 3 days and Malaysia's 72 hours are not the same deadline
Both look like the same breach-notification window, but the clocks start at different events. Singapore's three days beg...
What an ID number's check digit actually proves
The last character of most identity numbers is computed from the ones before it, using a published formula anyone can ap...
How to Stop ChatGPT, Claude, Gemini and Grok Training on Your Chats (2026)
Four switches with almost the same name, doing four different things. Three are on by default. One also sets your retent...
Which Image Operations Strip Metadata
A source image with six identifying tags and GPS coordinates, put through eight operations. Pillow drops everything unle...
How to Stop an Agent Returning Documents the User Should Not See
A vector search scoped three ways, and measured each time. Unfiltered, four in five results belonged to another team; fi...
First-Party, Third-Party: What the Cookie Labels Hide
Six public homepages, a fresh browser profile each, no banner answered: from 0 cookies to 54. But the count is the wrong...
What Can a Browser Extension See? We Read the Manifests
The permission dialogue tells you exactly what an extension may do, in a vocabulary that means little until you have see...
What Does Incognito Mode Actually Do? Less Than the Name Suggests
A private window destroys a storage container when you close it — five things go with it, all of them data your own devi...
What Is My IP Address, and What Does It Actually Reveal?
It identifies a connection, not a person. It gives away your country reliably, your network operator exactly, and — the...
How to Redact a PDF So the Text Is Actually Gone
A black rectangle removes nothing, and the check most people run afterwards returns nothing on a file that is leaking ba...
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