We knew that changes to the pattern unlock in Android 12 were coming, but the precise nature of those tweaks wasn't known until today. As of DP2, Android 12's pattern unlock system has new thicker lines with accented color and a "fun" new animation.
Left: Android 11. Right: Android 12 DP2
Android 11 and earlier (as well as Android 12 DP1) drew thin lines when drawing out your pattern unlock, but DP2 plumps that out with some seriously thick lines, tinted to match your configured style's accent color. It's a more fun look, but it also helps with accessibility: That thicker line is much easier to see and contrasts better as a color compared to the thin white line we had before.
Left: Android 11. Right: Android 12.
DP2 also brings a new animation when you input the wrong pattern as well. Instead of simply being told the pattern is incorrect with a tiny, almost unnoticeable bit of text all the way at the top of the screen and no other real visual indicator, DP2 has the grid flash orange-red, so you can more easily spot that something went wrong. (Also, it's just a little more fun.)
For more about Android 12, check out our ongoing series coverage here, or bookmark our regularly updated changelog and check back in later. If you want to install the developer preview on your own device, find out how in our Android 12 download guide.