textAppearCheckLine() runs synchronously from inside the width and
height animation tick callbacks (textAppearWidthCallback /
textAppearHeightCallback). Calling RemoveComponents(TextAppearing::Bit())
there destroys those very animations (and their Ui::Animations::Simple
data) while the animations manager is still iterating them, leading to a
use-after-free / null _data dereference in Simple::value().
Defer the component removal to the next main loop iteration so the
running tick can unwind first.
Denys Melnyk
24ccd1c92e