diff --git a/app/assets/javascripts/pretty-text/pretty-text.js.es6 b/app/assets/javascripts/pretty-text/pretty-text.js.es6
index 32064527aed..f341e7c4c7c 100644
--- a/app/assets/javascripts/pretty-text/pretty-text.js.es6
+++ b/app/assets/javascripts/pretty-text/pretty-text.js.es6
@@ -1,9 +1,10 @@
 import { cook as cookIt, setup as setupIt } from 'pretty-text/engines/discourse-markdown-it';
 
 export function registerOption() {
-  if (window.console) {
-    window.console.log("registerOption is deprecated");
-  }
+  // TODO next major version deprecate this
+  // if (window.console) {
+  //   window.console.log("registerOption is deprecated");
+  // }
 }
 
 export function buildOptions(state) {
diff --git a/plugins/discourse-details/assets/javascripts/lib/discourse-markdown/details.js.es6 b/plugins/discourse-details/assets/javascripts/lib/discourse-markdown/details.js.es6
index 4fb9b3d0f3b..602846062e2 100644
--- a/plugins/discourse-details/assets/javascripts/lib/discourse-markdown/details.js.es6
+++ b/plugins/discourse-details/assets/javascripts/lib/discourse-markdown/details.js.es6
@@ -1,25 +1,3 @@
-import { registerOption } from 'pretty-text/pretty-text';
-
-function insertDetails(_, summary, details) {
-  return `<details><summary>${summary}</summary>${details}</details>`;
-}
-
-// replace all [details] BBCode with HTML 5.1 equivalent
-function replaceDetails(text) {
-  text = text || "";
-
-  while (text !== (text = text.replace(/\[details=([^\]]+)\]((?:(?!\[details=[^\]]+\]|\[\/details\])[\S\s])*)\[\/details\]/ig, insertDetails)));
-
-  // add new lines to make sure we *always* have a <p> element after </summary> and around </details>
-  // otherwise we can't hide the content since we can't target text nodes via CSS
-  return text.replace(/<\/summary>/ig, "</summary>\n\n")
-             .replace(/<\/details>/ig, "\n\n</details>\n\n");
-}
-
-registerOption((siteSettings, opts) => {
-  opts.features.details = true;
-});
-
 const rule = {
   tag: 'details',
   before: function(state, attrs) {
@@ -46,11 +24,7 @@ export function setup(helper) {
     'details.elided'
   ]);
 
-  if (helper.markdownIt) {
-    helper.registerPlugin(md => {
-      md.block.bbcode_ruler.push('details', rule);
-    });
-  } else {
-    helper.addPreProcessor(text => replaceDetails(text));
-  }
+  helper.registerPlugin(md => {
+    md.block.bbcode_ruler.push('details', rule);
+  });
 }
diff --git a/plugins/discourse-details/test/javascripts/lib/details-cooked-test.js.es6 b/plugins/discourse-details/test/javascripts/lib/details-cooked-test.js.es6
index a1bd26c43d6..4087ea22b21 100644
--- a/plugins/discourse-details/test/javascripts/lib/details-cooked-test.js.es6
+++ b/plugins/discourse-details/test/javascripts/lib/details-cooked-test.js.es6
@@ -8,7 +8,7 @@ const defaultOpts = buildOptions({
     emoji_set: 'emoji_one',
     highlighted_languages: 'json|ruby|javascript',
     default_code_lang: 'auto',
-    censored_words: 'shucks|whiz|whizzer'
+    censored_words: ''
   },
   getURL: url => url
 });
@@ -19,17 +19,13 @@ test("details", assert => {
     assert.equal(new PrettyText(defaultOpts).cook(input), expected.replace(/\/>/g, ">"), text);
   };
   cooked(`<details><summary>Info</summary>coucou</details>`,
-         `<details><summary>Info</summary>\n\n<p>coucou</p>\n\n</details>`,
+         `<details><summary>Info</summary>coucou</details>`,
          "manual HTML for details");
-  cooked(` <details><summary>Info</summary>coucou</details>`,
-         `<details><summary>Info</summary>\n\n<p>coucou</p>\n\n</details>`,
-         "manual HTML for details with a space");
 
-  cooked(`<details open="open"><summary>Info</summary>coucou</details>`,
-         `<details open="open"><summary>Info</summary>\n\n<p>coucou</p>\n\n</details>`,
-         "open attribute");
-
-  cooked(`<details open><summary>Info</summary>coucou</details>`,
-         `<details open><summary>Info</summary>\n\n<p>coucou</p>\n\n</details>`,
-         "open attribute");
+  cooked("[details=testing]\ntest\n[/details]",
+`<details>
+<summary>
+testing</summary>
+<p>test</p>
+</details>`);
 });