low social media activity; rarely checking in
Internet slang describing someone who is not very active on social media, rarely posts, or seldom checks in. Often used self-deprecatingly or to describe a friend's online habits.
I've been on low activity lately and haven't been checking social media much.
彼は低浮上だから、返信が遅くても気にしないで。
He's rarely online, so don't worry if his replies are slow.
ROM専 refers to someone who only reads/lurks without posting; 低浮上 is broader, covering infrequent activity in general.
Compound of 低 (low) and 浮上 (surfacing, coming online). Likely coined in online communities to describe infrequent social media activity.