WebAuthn tells your server to ignore the bit that proves two factors
One flag distinguishes a passkey login that used only the device from one that also took a PIN or fingerprint. The spec...
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Apple's earbuds protect your hearing in America and merely reduce loud sound in Singapore
The same silicon, running the same firmware. Apple calls the feature Hearing Protection in the US and Loud Sound Reducti...
A TDS meter cannot measure total dissolved solids
Total dissolved solids is defined as a weight — filter, evaporate, weigh the residue at 180 °C. A handheld pen measures...
Four different electricity prices are printed on appliance labels in one shop
US regulations fix a refrigerator's running cost at 14 cents a kilowatt-hour, an air conditioner's at 13, a ceiling fan'...
Your osteoporosis diagnosis is scored against two different populations at once
The hip T-score is computed against a US survey of white women aged 20–29 measured in 1988–94; the spine T-score against...
Malaysia says an e-invoice needs 55 fields; its own appendix marks 20 optional
The tax authority's guideline states that 55 data fields are required to issue an e-invoice. The appendix listing those...
One embedding model, four different maximum lengths
The most downloaded sentence-embedding model ships four config files declaring 128, 256, 512 and 512 as its maximum inpu...
Vietnam deleted the rule that made its ID numbers decodable, and nobody stopped decoding them
Since 1 July 2024 no Vietnamese instrument says the 12-digit citizen ID has any internal structure. The decree defining...
The annual Sharpe ratio hides an assumption about your returns
Annualising a monthly Sharpe ratio by multiplying by the square root of twelve is not a unit conversion. It is Andrew Lo...
One sky, three verdicts: why Singapore says unhealthy and Malaysia says moderate
The same 70 micrograms of fine particulate reads 116 on Singapore's PSI, 96 on Malaysia's API and 161 on the US AQI. Alm...
Malaysia banned the Rule of 78, and the Rule of 78 was never the expensive part
On Bank Negara's own worked example the Rule of 78 costs an early settler at most about RM632 on a RM100,000 loan. Readi...
The DMARC tag that meant 10% of the time now means all the time
RFC 9989 removed the pct tag in May 2026, and the same document says receivers must ignore tags that are not registered....
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