✨ ベストアンサー ✨
Yes, this sentence is correct. "to pop in" is a "phrasal verb" which means it has a fixed preposition[前置詞]. Some of these "phrasal verbs" can be combined with other prepositions.
to pop in == to make a short visit
He (popped in) (at the beauty parlor).
The famous actor (popped in) (in the final episode of the season).
She (popped in) (in the middle of the night).
Other examples:
to look up [仰ぐ] → He (looks up) (to his teacher).
to look down [見下ろす] → The haughty king (looked down) (on his subjects).
to kneel down → He (knelt down) (before her).
