fix preload bug

js/controllers/slidecontent.js

@@ -25,8 +25,12 @@ export default class SlideContent {
 	 */
 	shouldPreload( element ) {
 
+		if( this.Reveal.isReaderMode() ) {
+			return true;
+		}
+
 		// Prefer an explicit global preload setting
-		let preload = this.Reveal.getConfig().preloadIframes || this.Reveal.isReaderMode();
+		let preload = this.Reveal.getConfig().preloadIframes;
 
 		// If no global setting is available, fall back on the element's
 		// own preload setting

package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "reveal.js",
-  "version": "4.5.0",
+  "version": "4.6.0",
   "lockfileVersion": 2,
   "requires": true,
   "packages": {
     "": {
       "name": "reveal.js",
-      "version": "4.5.0",
+      "version": "4.6.0",
       "license": "MIT",
       "devDependencies": {
         "@babel/core": "^7.14.3",
@@ -2197,26 +2197,35 @@
       }
     },
     "node_modules/browserslist": {
-      "version": "4.19.3",
-      "resolved": "https://registry.npmjs.org/browserslist/-/browserslist-4.19.3.tgz",
-      "integrity": "sha512-XK3X4xtKJ+Txj8G5c30B4gsm71s69lqXlkYui4s6EkKxuv49qjYlY6oVd+IFJ73d4YymtM3+djvvt/R/iJwwDg==",
+      "version": "4.21.10",
+      "resolved": "https://registry.npmjs.org/browserslist/-/browserslist-4.21.10.tgz",
+      "integrity": "sha512-bipEBdZfVH5/pwrvqc+Ub0kUPVfGUhlKxbvfD+z1BDnPEO/X98ruXGA1WP5ASpAFKan7Qr6j736IacbZQuAlKQ==",
       "dev": true,
+      "funding": [
+        {
+          "type": "opencollective",
+          "url": "https://opencollective.com/browserslist"
+        },
+        {
+          "type": "tidelift",
+          "url": "https://tidelift.com/funding/github/npm/browserslist"
+        },
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/ai"
+        }
+      ],
       "dependencies": {
-        "caniuse-lite": "^1.0.30001312",
-        "electron-to-chromium": "^1.4.71",
-        "escalade": "^3.1.1",
-        "node-releases": "^2.0.2",
-        "picocolors": "^1.0.0"
+        "caniuse-lite": "^1.0.30001517",
+        "electron-to-chromium": "^1.4.477",
+        "node-releases": "^2.0.13",
+        "update-browserslist-db": "^1.0.11"
       },
       "bin": {
         "browserslist": "cli.js"
       },
       "engines": {
         "node": "^6 || ^7 || ^8 || ^9 || ^10 || ^11 || ^12 || >=13.7"
-      },
-      "funding": {
-        "type": "opencollective",
-        "url": "https://opencollective.com/browserslist"
       }
     },
     "node_modules/buffer": {
@@ -2337,9 +2346,9 @@
       }
     },
     "node_modules/caniuse-lite": {
-      "version": "1.0.30001374",
-      "resolved": "https://registry.npmjs.org/caniuse-lite/-/caniuse-lite-1.0.30001374.tgz",
-      "integrity": "sha512-mWvzatRx3w+j5wx/mpFN5v5twlPrabG8NqX2c6e45LCpymdoGqNvRkRutFUqpRTXKFQFNQJasvK0YT7suW6/Hw==",
+      "version": "1.0.30001538",
+      "resolved": "https://registry.npmjs.org/caniuse-lite/-/caniuse-lite-1.0.30001538.tgz",
+      "integrity": "sha512-HWJnhnID+0YMtGlzcp3T9drmBJUVDchPJ08tpUGFLs9CYlwWPH2uLgpHn8fND5pCgXVtnGS3H4QR9XLMHVNkHw==",
       "dev": true,
       "funding": [
         {
@@ -2349,6 +2358,10 @@
         {
           "type": "tidelift",
           "url": "https://tidelift.com/funding/github/npm/caniuse-lite"
+        },
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/ai"
         }
       ]
     },
@@ -2854,28 +2867,18 @@
       }
     },
     "node_modules/core-js-compat": {
-      "version": "3.12.1",
-      "resolved": "https://registry.npmjs.org/core-js-compat/-/core-js-compat-3.12.1.tgz",
-      "integrity": "sha512-i6h5qODpw6EsHAoIdQhKoZdWn+dGBF3dSS8m5tif36RlWvW3A6+yu2S16QHUo3CrkzrnEskMAt9f8FxmY9fhWQ==",
+      "version": "3.32.2",
+      "resolved": "https://registry.npmjs.org/core-js-compat/-/core-js-compat-3.32.2.tgz",
+      "integrity": "sha512-+GjlguTDINOijtVRUxrQOv3kfu9rl+qPNdX2LTbJ/ZyVTuxK+ksVSAGX1nHstu4hrv1En/uPTtWgq2gI5wt4AQ==",
       "dev": true,
       "dependencies": {
-        "browserslist": "^4.16.6",
-        "semver": "7.0.0"
+        "browserslist": "^4.21.10"
       },
       "funding": {
         "type": "opencollective",
         "url": "https://opencollective.com/core-js"
       }
     },
-    "node_modules/core-js-compat/node_modules/semver": {
-      "version": "7.0.0",
-      "resolved": "https://registry.npmjs.org/semver/-/semver-7.0.0.tgz",
-      "integrity": "sha512-+GB6zVA9LWh6zovYQLALHwv5rb2PHGlJi3lfiqIHxR0uuwCgefcOJc59v9fv1w8GbStwxuuqqAjI9NMAOOgq1A==",
-      "dev": true,
-      "bin": {
-        "semver": "bin/semver.js"
-      }
-    },
     "node_modules/core-util-is": {
       "version": "1.0.2",
       "resolved": "https://registry.npmjs.org/core-util-is/-/core-util-is-1.0.2.tgz",
@@ -3155,9 +3158,9 @@
       "dev": true
     },
     "node_modules/electron-to-chromium": {
-      "version": "1.4.73",
-      "resolved": "https://registry.npmjs.org/electron-to-chromium/-/electron-to-chromium-1.4.73.tgz",
-      "integrity": "sha512-RlCffXkE/LliqfA5m29+dVDPB2r72y2D2egMMfIy3Le8ODrxjuZNVo4NIC2yPL01N4xb4nZQLwzi6Z5tGIGLnA==",
+      "version": "1.4.526",
+      "resolved": "https://registry.npmjs.org/electron-to-chromium/-/electron-to-chromium-1.4.526.tgz",
+      "integrity": "sha512-tjjTMjmZAx1g6COrintLTa2/jcafYKxKoiEkdQOrVdbLaHh2wCt2nsAF8ZHweezkrP+dl/VG9T5nabcYoo0U5Q==",
       "dev": true
     },
     "node_modules/emoji-regex": {
@@ -3476,9 +3479,9 @@
       }
     },
     "node_modules/eslint/node_modules/semver": {
-      "version": "7.3.5",
-      "resolved": "https://registry.npmjs.org/semver/-/semver-7.3.5.tgz",
-      "integrity": "sha512-PoeGJYh8HK4BTO/a9Tf6ZG3veo/A7ZVsYrSA6J8ny9nb3B1VrpkuN+z9OE5wfE5p6H4LchYZsegiQgbJD94ZFQ==",
+      "version": "7.5.4",
+      "resolved": "https://registry.npmjs.org/semver/-/semver-7.5.4.tgz",
+      "integrity": "sha512-1bCSESV6Pv+i21Hvpxp3Dx+pSD8lIPt8uVjRrxAUt/nbswYc+tK6Y2btiULjd4+fnq15PX+nqQDC7Oft7WkwcA==",
       "dev": true,
       "peer": true,
       "dependencies": {
@@ -4754,9 +4757,9 @@
       }
     },
     "node_modules/gulp-eslint/node_modules/cross-spawn/node_modules/semver": {
-      "version": "5.7.1",
-      "resolved": "https://registry.npmjs.org/semver/-/semver-5.7.1.tgz",
-      "integrity": "sha512-sauaDf/PZdVgrLTNYHRtpXa1iRiKcaebiKQ1BJdpQlWH2lCvexQdX55snPFyK7QzpudqbCI0qXFfOasHdyNDGQ==",
+      "version": "5.7.2",
+      "resolved": "https://registry.npmjs.org/semver/-/semver-5.7.2.tgz",
+      "integrity": "sha512-cBznnQ9KjJqU67B52RMC65CMarK2600WFnbkcaiwWq3xy/5haFJlshgnpjovMVJ+Hff49d8GEn0b87C5pDQ10g==",
       "dev": true,
       "bin": {
         "semver": "bin/semver"
@@ -6591,9 +6594,9 @@
       }
     },
     "node_modules/node-releases": {
-      "version": "2.0.2",
-      "resolved": "https://registry.npmjs.org/node-releases/-/node-releases-2.0.2.tgz",
-      "integrity": "sha512-XxYDdcQ6eKqp/YjI+tb2C5WM2LgjnZrfYg4vgQt49EK268b6gYCHsBLrK2qvJo4FmCtqmKezb0WZFK4fkrZNsg==",
+      "version": "2.0.13",
+      "resolved": "https://registry.npmjs.org/node-releases/-/node-releases-2.0.13.tgz",
+      "integrity": "sha512-uYr7J37ae/ORWdZeQ1xxMJe3NtdmqMC/JZK+geofDrkLUApKRHPd18/TxtBOJ4A0/+uUIliorNrfYV6s1b02eQ==",
       "dev": true
     },
     "node_modules/node-watch": {
@@ -6618,9 +6621,9 @@
       }
     },
     "node_modules/normalize-package-data/node_modules/semver": {
-      "version": "5.7.1",
-      "resolved": "https://registry.npmjs.org/semver/-/semver-5.7.1.tgz",
-      "integrity": "sha512-sauaDf/PZdVgrLTNYHRtpXa1iRiKcaebiKQ1BJdpQlWH2lCvexQdX55snPFyK7QzpudqbCI0qXFfOasHdyNDGQ==",
+      "version": "5.7.2",
+      "resolved": "https://registry.npmjs.org/semver/-/semver-5.7.2.tgz",
+      "integrity": "sha512-cBznnQ9KjJqU67B52RMC65CMarK2600WFnbkcaiwWq3xy/5haFJlshgnpjovMVJ+Hff49d8GEn0b87C5pDQ10g==",
       "dev": true,
       "bin": {
         "semver": "bin/semver"
@@ -7966,9 +7969,9 @@
       }
     },
     "node_modules/semver": {
-      "version": "6.3.0",
-      "resolved": "https://registry.npmjs.org/semver/-/semver-6.3.0.tgz",
-      "integrity": "sha512-b39TBaTSfV6yBrapU89p5fKekE2m/NwnDocOVruQFS1/veMgdzuPcnOM34M6CwxW8jH/lxEa5rBoDeUwu5HHTw==",
+      "version": "6.3.1",
+      "resolved": "https://registry.npmjs.org/semver/-/semver-6.3.1.tgz",
+      "integrity": "sha512-BR7VvDCVHO+q2xBEWskxS6DJE1qRnb7DxzUrogb71CWoSficBxYsiAGd+Kl0mmq/MprG9yArRkyrQxTO6XjMzA==",
       "dev": true,
       "bin": {
         "semver": "bin/semver.js"
@@ -9406,6 +9409,36 @@
         "node": ">=0.10.0"
       }
     },
+    "node_modules/update-browserslist-db": {
+      "version": "1.0.12",
+      "resolved": "https://registry.npmjs.org/update-browserslist-db/-/update-browserslist-db-1.0.12.tgz",
+      "integrity": "sha512-tE1smlR58jxbFMtrMpFNRmsrOXlpNXss965T1CrpwuZUzUAg/TBQc94SpyhDLSzrqrJS9xTRBthnZAGcE1oaxg==",
+      "dev": true,
+      "funding": [
+        {
+          "type": "opencollective",
+          "url": "https://opencollective.com/browserslist"
+        },
+        {
+          "type": "tidelift",
+          "url": "https://tidelift.com/funding/github/npm/browserslist"
+        },
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/ai"
+        }
+      ],
+      "dependencies": {
+        "escalade": "^3.1.1",
+        "picocolors": "^1.0.0"
+      },
+      "bin": {
+        "update-browserslist-db": "cli.js"
+      },
+      "peerDependencies": {
+        "browserslist": ">= 4.21.0"
+      }
+    },
     "node_modules/uri-js": {
       "version": "4.4.1",
       "resolved": "https://registry.npmjs.org/uri-js/-/uri-js-4.4.1.tgz",
@@ -9629,9 +9662,9 @@
       "dev": true
     },
     "node_modules/word-wrap": {
-      "version": "1.2.3",
-      "resolved": "https://registry.npmjs.org/word-wrap/-/word-wrap-1.2.3.tgz",
-      "integrity": "sha512-Hz/mrNwitNRh/HUAtM/VT/5VH+ygD6DV7mYKZAtHOrbs8U7lvPS6xf7EJKMF0uW1KJCl0H701g3ZGus+muE5vQ==",
+      "version": "1.2.5",
+      "resolved": "https://registry.npmjs.org/word-wrap/-/word-wrap-1.2.5.tgz",
+      "integrity": "sha512-BN22B5eaMMI9UMtjrGd5g5eCYPpCPDUy0FJXbYsaT5zYxjFOckS53SQDE3pWkVoWpHXVb3BrYcEN4Twa55B5cA==",
       "dev": true,
       "engines": {
         "node": ">=0.10.0"
@@ -11529,16 +11562,15 @@
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     },
     "browserslist": {
-      "version": "4.19.3",
-      "resolved": "https://registry.npmjs.org/browserslist/-/browserslist-4.19.3.tgz",
-      "integrity": "sha512-XK3X4xtKJ+Txj8G5c30B4gsm71s69lqXlkYui4s6EkKxuv49qjYlY6oVd+IFJ73d4YymtM3+djvvt/R/iJwwDg==",
+      "version": "4.21.10",
+      "resolved": "https://registry.npmjs.org/browserslist/-/browserslist-4.21.10.tgz",
+      "integrity": "sha512-bipEBdZfVH5/pwrvqc+Ub0kUPVfGUhlKxbvfD+z1BDnPEO/X98ruXGA1WP5ASpAFKan7Qr6j736IacbZQuAlKQ==",
       "dev": true,
       "requires": {
-        "caniuse-lite": "^1.0.30001312",
-        "electron-to-chromium": "^1.4.71",
-        "escalade": "^3.1.1",
-        "node-releases": "^2.0.2",
-        "picocolors": "^1.0.0"
+        "caniuse-lite": "^1.0.30001517",
+        "electron-to-chromium": "^1.4.477",
+        "node-releases": "^2.0.13",
+        "update-browserslist-db": "^1.0.11"
       }
     },
     "buffer": {
@@ -11621,9 +11653,9 @@
       "dev": true
     },
     "caniuse-lite": {
-      "version": "1.0.30001374",
-      "resolved": "https://registry.npmjs.org/caniuse-lite/-/caniuse-lite-1.0.30001374.tgz",
-      "integrity": "sha512-mWvzatRx3w+j5wx/mpFN5v5twlPrabG8NqX2c6e45LCpymdoGqNvRkRutFUqpRTXKFQFNQJasvK0YT7suW6/Hw==",
+      "version": "1.0.30001538",
+      "resolved": "https://registry.npmjs.org/caniuse-lite/-/caniuse-lite-1.0.30001538.tgz",
+      "integrity": "sha512-HWJnhnID+0YMtGlzcp3T9drmBJUVDchPJ08tpUGFLs9CYlwWPH2uLgpHn8fND5pCgXVtnGS3H4QR9XLMHVNkHw==",
       "dev": true
     },
     "chalk": {
@@ -12036,21 +12068,12 @@
       "dev": true
     },
     "core-js-compat": {
-      "version": "3.12.1",
-      "resolved": "https://registry.npmjs.org/core-js-compat/-/core-js-compat-3.12.1.tgz",
-      "integrity": "sha512-i6h5qODpw6EsHAoIdQhKoZdWn+dGBF3dSS8m5tif36RlWvW3A6+yu2S16QHUo3CrkzrnEskMAt9f8FxmY9fhWQ==",
+      "version": "3.32.2",
+      "resolved": "https://registry.npmjs.org/core-js-compat/-/core-js-compat-3.32.2.tgz",
+      "integrity": "sha512-+GjlguTDINOijtVRUxrQOv3kfu9rl+qPNdX2LTbJ/ZyVTuxK+ksVSAGX1nHstu4hrv1En/uPTtWgq2gI5wt4AQ==",
       "dev": true,
       "requires": {
-        "browserslist": "^4.16.6",
-        "semver": "7.0.0"
-      },
-      "dependencies": {
-        "semver": {
-          "version": "7.0.0",
-          "resolved": "https://registry.npmjs.org/semver/-/semver-7.0.0.tgz",
-          "integrity": "sha512-+GB6zVA9LWh6zovYQLALHwv5rb2PHGlJi3lfiqIHxR0uuwCgefcOJc59v9fv1w8GbStwxuuqqAjI9NMAOOgq1A==",
-          "dev": true
-        }
+        "browserslist": "^4.21.10"
       }
     },
     "core-util-is": {
@@ -12277,9 +12300,9 @@
       "dev": true
     },
     "electron-to-chromium": {
-      "version": "1.4.73",
-      "resolved": "https://registry.npmjs.org/electron-to-chromium/-/electron-to-chromium-1.4.73.tgz",
-      "integrity": "sha512-RlCffXkE/LliqfA5m29+dVDPB2r72y2D2egMMfIy3Le8ODrxjuZNVo4NIC2yPL01N4xb4nZQLwzi6Z5tGIGLnA==",
+      "version": "1.4.526",
+      "resolved": "https://registry.npmjs.org/electron-to-chromium/-/electron-to-chromium-1.4.526.tgz",
+      "integrity": "sha512-tjjTMjmZAx1g6COrintLTa2/jcafYKxKoiEkdQOrVdbLaHh2wCt2nsAF8ZHweezkrP+dl/VG9T5nabcYoo0U5Q==",
       "dev": true
     },
     "emoji-regex": {
@@ -12505,9 +12528,9 @@
           "peer": true
         },
         "semver": {
-          "version": "7.3.5",
-          "resolved": "https://registry.npmjs.org/semver/-/semver-7.3.5.tgz",
-          "integrity": "sha512-PoeGJYh8HK4BTO/a9Tf6ZG3veo/A7ZVsYrSA6J8ny9nb3B1VrpkuN+z9OE5wfE5p6H4LchYZsegiQgbJD94ZFQ==",
+          "version": "7.5.4",
+          "resolved": "https://registry.npmjs.org/semver/-/semver-7.5.4.tgz",
+          "integrity": "sha512-1bCSESV6Pv+i21Hvpxp3Dx+pSD8lIPt8uVjRrxAUt/nbswYc+tK6Y2btiULjd4+fnq15PX+nqQDC7Oft7WkwcA==",
           "dev": true,
           "peer": true,
           "requires": {
@@ -13577,9 +13600,9 @@
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           "dependencies": {
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-              "version": "5.7.1",
-              "resolved": "https://registry.npmjs.org/semver/-/semver-5.7.1.tgz",
-              "integrity": "sha512-sauaDf/PZdVgrLTNYHRtpXa1iRiKcaebiKQ1BJdpQlWH2lCvexQdX55snPFyK7QzpudqbCI0qXFfOasHdyNDGQ==",
+              "version": "5.7.2",
+              "resolved": "https://registry.npmjs.org/semver/-/semver-5.7.2.tgz",
+              "integrity": "sha512-cBznnQ9KjJqU67B52RMC65CMarK2600WFnbkcaiwWq3xy/5haFJlshgnpjovMVJ+Hff49d8GEn0b87C5pDQ10g==",
               "dev": true
             }
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@@ -15023,9 +15046,9 @@
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-      "version": "2.0.2",
-      "resolved": "https://registry.npmjs.org/node-releases/-/node-releases-2.0.2.tgz",
-      "integrity": "sha512-XxYDdcQ6eKqp/YjI+tb2C5WM2LgjnZrfYg4vgQt49EK268b6gYCHsBLrK2qvJo4FmCtqmKezb0WZFK4fkrZNsg==",
+      "version": "2.0.13",
+      "resolved": "https://registry.npmjs.org/node-releases/-/node-releases-2.0.13.tgz",
+      "integrity": "sha512-uYr7J37ae/ORWdZeQ1xxMJe3NtdmqMC/JZK+geofDrkLUApKRHPd18/TxtBOJ4A0/+uUIliorNrfYV6s1b02eQ==",
       "dev": true
     },
     "node-watch": {
@@ -15047,9 +15070,9 @@
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       "dependencies": {
         "semver": {
-          "version": "5.7.1",
-          "resolved": "https://registry.npmjs.org/semver/-/semver-5.7.1.tgz",
-          "integrity": "sha512-sauaDf/PZdVgrLTNYHRtpXa1iRiKcaebiKQ1BJdpQlWH2lCvexQdX55snPFyK7QzpudqbCI0qXFfOasHdyNDGQ==",
+          "version": "5.7.2",
+          "resolved": "https://registry.npmjs.org/semver/-/semver-5.7.2.tgz",
+          "integrity": "sha512-cBznnQ9KjJqU67B52RMC65CMarK2600WFnbkcaiwWq3xy/5haFJlshgnpjovMVJ+Hff49d8GEn0b87C5pDQ10g==",
           "dev": true
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@@ -16081,9 +16104,9 @@
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-      "version": "6.3.0",
-      "resolved": "https://registry.npmjs.org/semver/-/semver-6.3.0.tgz",
-      "integrity": "sha512-b39TBaTSfV6yBrapU89p5fKekE2m/NwnDocOVruQFS1/veMgdzuPcnOM34M6CwxW8jH/lxEa5rBoDeUwu5HHTw==",
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+      "resolved": "https://registry.npmjs.org/semver/-/semver-6.3.1.tgz",
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       "dev": true
     },
     "semver-greatest-satisfied-range": {
@@ -17299,6 +17322,16 @@
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+    "update-browserslist-db": {
+      "version": "1.0.12",
+      "resolved": "https://registry.npmjs.org/update-browserslist-db/-/update-browserslist-db-1.0.12.tgz",
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+      "resolved": "https://registry.npmjs.org/word-wrap/-/word-wrap-1.2.5.tgz",
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