With the introduction of a new Rules Editor in Altium Designer 21, violations of design constraint rules are now displayed in the Rules Editor itself. Here's how.

Enabled design constraint rules are applied to the current board design through a range of mechanisms, such as live Online Design Rule Checking, the batch Design Rule Checker or selectively run from the PCB Rules and Violations panel. 

Violations of those constraint Rules – where the specified and scoped limits are exceeded – are indicated through board graphics, panel entries and reports. With the introduction of a new Rules Editor in Altium Designer 21, violations of these rules are now displayed in the Rules Editor itself.

And as a bonus, violations can be inspected, analyzed, and corrected while the Rules Editor is open, thanks to its design document (rather than dialog) format.