Title text:
Other numbers are largely unaffected, but anyone using '4' for their certificate key is urged to upgrade to '5'.
Transcript:
Transcript will show once it’s been added to explainxkcd.com
Source: https://xkcd.com/3314/
puts on novelty slinky eye glasses
Fascinating.
Also, small thing:
3*1 - 0.5*1 = 3 - 0.5 = 2.5
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