How to remove the "3D print with 3D Builder" context menu entry in Windows 10?
I monitored what was happening under the hood when right clicking an image file (with the tool Process Monitor from SysInternals), and found out the responsible registry keys.
It is displayed because of the "T3D Print" shell key in bmp, jpg and png file types associations:
HKLM\SOFTWARE\Classes\SystemFileAssociations\.bmp\Shell\T3D Print
HKLM\SOFTWARE\Classes\SystemFileAssociations\.jpg\Shell\T3D Print
HKLM\SOFTWARE\Classes\SystemFileAssociations\.png\Shell\T3D Print
Deleting them immediately removes the 3D print with 3D Builder item from the context menu.
Just in case, make sure to backup the keys beforehand, to be able to revert the changes.