Image showing the 3 mm continuum emission in the area of DR21 Main. The peak of the continuum emission is marked with a red star, while the green circle marks the location of the dense core DR21-1 (Cao et al. 2019), and the green dashed line the FWHM. Blue contours mark the integrated HCO⁺ intensity (−50 to 50 km s⁻¹), while the beam of the continuum observations is shown with the red ellipse.