akkoma/priv/static/embed/embed.js

(function () {
  'use strict'

  var ready = function (loaded) {
    if (['interactive', 'complete'].indexOf(document.readyState) !== -1) {
      loaded()
    } else {
      document.addEventListener('DOMContentLoaded', loaded)
    }
  }

  ready(function () {
    var iframes = []

    window.addEventListener('message', function (e) {
      var data = e.data || {}

      if (data.type !== 'setHeightPleromaEmbed' || !iframes[data.id]) {
        return
      }

      iframes[data.id].height = data.height
    });

    [].forEach.call(document.querySelectorAll('iframe.pleroma-embed'), function (iframe) {
      iframe.scrolling = 'no'
      iframe.style.overflow = 'hidden'

      iframes.push(iframe)

      var id = iframes.length - 1

      iframe.onload = function () {
        iframe.contentWindow.postMessage({
          type: 'setHeightPleromaEmbed',
          id: id
        }, '*')
      }

      iframe.onload()
    })
  })
})()