A pedophile dogwhistle term created by a self-admitted pedophile who repeatedly voices his support for both non-offending and offending pedophiles as well as encouraging CSA survivors to commit crimes themselves and continue the cycle of abuse.
The term is essentially "anti-monstricide," where "monstricide" - a term coined by Youtuber MamaMax - means the violent punishing of pedophiles and animal abusers (usually as an act of vigilantism) typically with the goal of protecting children and animals as much as possible. "Vigistride" is then, as the pedophile creator of the term describes, when pedophiles go after pedo hunters with violent intent.
John: Hey, you hear that some pedo with a hate-boner for pedo hunters brags about wanting to murder 'em?
Sally: Oh yeah, he posts pictures of baseball bats covered in fake blood, threatening to kill them or whatever. "Vigistride," he calls it. I'm pretty sure it isn't even a real word.