I’ve learned the hard way that Metallica fans can spot a “signal” in the tiniest detail. A new font. A shifted shade. A logo nudged two pixels to the left. So when the band quietly revamped the look of its social media accounts on Tuesday, it didn’t feel like a simple design tweak—it felt like someone had moved the furniture in a house we all know by heart. And of course the question followed immediately: Are they about to announce something big?