I like that English and French have a similar thing going on with the sayings “He isn’t the sharpest tool in the shed” and “Il n’a pas inventé l’eau chaude” (he didn’t invent hot water). In both cases there are many established variants; some are quite normal (not the brightest bulb in the box / “il n’a pas inventé la poudre à canon”, he didn’t invent gunpowder), then you can make it a bit sillier, “he isn’t the crunchiest chip in the bag / quickest bunny in the forest”, “il n’a pas inventé le fil à couper le beurre / la machine à courber les bananes” (he didn’t invent the butter slicer wire / the banana-curving machine), and we also both enjoy making them absurd via crossbreeding (he isn’t the sharpest bunny in the box / il n’a pas inventé le fil à couper l’eau chaude - he didn’t invent the hot water slicer wire) and so on and so forth