Answer:

popup

Answer	Crossword Clue
POPUP	Type of children's book
POPUP	Easy-to-nab fly
POPUP	Unchallenging fly

POPUP	Like books with interesting openings?
POPUP	Arise without warning
POPUP	Unexpectedly materialize
POPUP	Online intrusion
POPUP	Blocker target
POPUP	Like some children's books
POPUP	Appear out of nowhere
POPUP	Like some kids' books

POPUP	Toaster type
POPUP	"... Video" (VH1 series)
POPUP	Easy out
POPUP	Type of Internet ad
POPUP	Easy out, typically
POPUP	Infield fly
POPUP	Annoying Web page ad
POPUP	Appear suddenly

POPUP	Easy fly ball
POPUP	High fly to the shortstop
POPUP	Suddenly appear
POPUP	Type of fly
POPUP	Web page ad
POPUP	Ball hit into air without much force, offering easy chance for catch.
POPUP	Type of illustration in juveniles.
POPUP	Appear unexpectedly.

POPUP	Describing a toaster's action.
POPUP	Type of toaster.
POPUP	Infield fly, in baseball.
POPUP	High fly ball, on the diamond.
POPUP	Appear suddenly.
POPUP	Adjective for an appliance.
POPUP	Kind of toaster.
POPUP	Infield fly.

POPUP	Infield out.
POPUP	Easy baseball out.
POPUP	Easy out, in a game.
POPUP	Toaster type.
POPUP	Diamond fly