Summary

I modified the 'Improved Low-Voltage Bracket' from Riskable that improved the original design from Lilfonzy

I lengthened the screw support, added ridges to the arms to bite into the drywall better, and put a brim on the face plate screw holes to help guide the screws.

I also made two version of the bracket, one with a 0.6mm thick face and the other left the original thickness of 1mm. I found the 0.6mm face to be just as strong so far, but it might not be so it's your choice

Used #6 x 1 1/2" flat head screws

Print ABS, ASA, or PC, three walls, 30% Grid infill. With minimal cooling