Unknown module(s) in QT: core gui quick

Question

I installed Pop!_OS 21.04 (based on Ubuntu Hirsute), and I'm trying to build a QML app I programmed on FreeBSD. qmake doesn't make the project, complaining that:

error: Project ERROR: Unknown module(s) in QT: core gui quick

I installed Qt Creator through apt.

KDE works fine, so does LXQt. Flatpak Qt Creator also works.

The same issue happens on Debian, so I'm assuming it'll happen in every Debian-based OS.

Answer 1

This is the solution that worked from above comments: Per @Egg:

Debian 11: sudo apt-get install qtbase5-dev