Method getParticleByParser

external/.scrollLibs.js:16742–16744

(parser)

    return parent instanceof parser ? parent : parent.getAncestorByParser(parser)
  }
  getParticleByParser(parser) {
    return this.find(subparticle => subparticle instanceof parser)
  }
  // todo: switch to native classes and parsers in particles and away from javascript classes for parsing.
  // move off particle.ts
  // make the below work.