In a recent design I had rule violations I was not aware of until ordering boards because teardrops added in did not generate errors on spacing violations, even when they were causing a direct short. I would have to consider this a significant defect in UB.
UB14.1 Win10 64b
Discussion and spacing violation with no errors shown here:
https://forums.ni.com/t5/Multisim-and-Ultiboard/Teardrops-and-design-rule-errors/td-p/3684720
