Method getSubparticlesByParser

external/.scrollLibs.js:16733–16735

(parser)

    return this.map(particle => particle.content)
  }
  getSubparticlesByParser(parser) {
    return this.filter(subparticle => subparticle instanceof parser)
  }
  getAncestorByParser(parser) {
    if (this instanceof parser) return this
    if (this.isRoot()) return undefined