The French flag
Today I learned that the French flag, the tricolour, has changed on 13th of July 2020. No substantial change, just a switch from the version introduced in 1976 that had a slightly lighter blue and red, to match the colours of the flag of the European Union, to the original, darker colours that were used for the tricolour during the French revolution and even since 1976 by the French navy.
I came across this after seeing a post about it in a matrix room about travelling, that linked a video talking about it. With some further investigation into their sources, it was a quite interesting detail to learn.
Note: Interestingly, even though many news articles claim that the 1976 adjustment of the colours was due to matching the Flag of the European Union, I couldn’t find any primary source for this claim in my limited research time and absence of French skills.