Detect pseudo class :invalid from javascript

[smarketing]

Is there a way to detect the "appearance" of the pseudo-class \[code\]:invalid\[/code\] on an \[code\]input\[/code\] element through Javascript?In other words, how could some Javascript code be triggered to run when the \[code\]:invalid\[/code\] pseudo-class appears on an \[code\]input\[/code\] element?