I'm actually astonished at how incredibly awful and broken After Effects is at this point. It blows my mind how a single program could have so. many. bugs. that Adobe is either blissfuly ignorant of, or just doesn't care. The liquify tool flat out doesn't work in any comp window on my project - I'll select any of the distort tools, but nothing will happen; I'll drag my cursor over the comp window, and the brush won't appear - dragging the mouse around will only move the layer. There are 5 other threads describing the same exact issue, and there are no solutions.
And it worked perfectly fine for me (and presumably every one else in all the linked posts) as well until it randomly decided it didn't want to anymore. New projects? Works just fine. Re-launch a project it randomly stopped working on? Kaput.