Factual error: There is a periodic table shown in the background of the lab, showing an accurate periodic table as of now. During 1945, at least 21 elements had not been discovered. (00:17:40)
Factual error: The Marine Colonel in Supergirl played by Eddie McClintock spends all of his time wearing Marine Officer's Dress Blue Bravos. Marine Dress Blues are ceremonial uniforms. On rare occasions, the Charlies or Deltas (no coat) may be worn as a work uniforms (the primary exception to this rareness being recruiters). The full uniform is certainly not worn for day to day work in the field.
Factual error: 1-1 A couple of spelling errors. A "community center" in Ceylon, a British colony, using the American instead of the British spelling. And Columbo listed as the capital of Ceylon; it's Colombo.
The Left Hand of the Magician - S1-E5
Factual error: Interviewing the circus crowd, Lupin talks with a guy that is counting a bunch of 5 euro banknotes. The notes lack serial numbers, but even if we consider okay the lack of detail in such a tight close-up where they bothered to reproduce with pretty good precision the rest of the filigree, they surely are shaped wrong, being at least a 30% wider than an actual 5 € note. (00:06:40)