diff --git a/TODO b/TODO
index 2301f0577..b200b75b3 100644
--- a/TODO
+++ b/TODO
@@ -5,9 +5,15 @@
   - Have updated column resizing to set cell widths
     - Now need to handle table overall size on change, then heights. 
 
+- Details/Summary
+  - Need view to control summary editability, make readonly but editable via popover.
+  - Need some default styles to visualise details boundary.
+  - Markdown parser needs to be updated to handle separate open/close tags for blocks. 
+
 ### In-Progress
 
 - Tables
+- Details/Summary
 
 ### Features
 
@@ -17,7 +23,6 @@
 - Fullscreen
 - Paste Image Uploading
 - Drag + Drop Image Uploading
-- Details/Summary
 - Checkbox/TODO list items
 - Code blocks
 - Indents
diff --git a/resources/js/editor/markdown-serializer.js b/resources/js/editor/markdown-serializer.js
index c0e3fcb0f..57d8484dc 100644
--- a/resources/js/editor/markdown-serializer.js
+++ b/resources/js/editor/markdown-serializer.js
@@ -17,6 +17,14 @@ nodes.iframe = function (state, node) {
     writeNodeAsHtml(state, node);
 };
 
+nodes.details = function (state, node) {
+    wrapNodeWithHtml(state, node, '<details>', '</details>');
+};
+
+nodes.details_summary = function(state, node) {
+    writeNodeAsHtml(state, node);
+};
+
 function isPlainURL(link, parent, index, side) {
     if (link.attrs.title || !/^\w+:/.test(link.attrs.href)) {
         return false
@@ -85,7 +93,7 @@ marks.background_color = {
 
 /**
  * @param {MarkdownSerializerState} state
- * @param node
+ * @param {PmNode} node
  */
 function writeNodeAsHtml(state, node) {
     const html = docToHtml({content: [node]});
@@ -95,6 +103,22 @@ function writeNodeAsHtml(state, node) {
     state.closeBlock();
 }
 
+/**
+ * @param {MarkdownSerializerState} state
+ * @param {PmNode} node
+ * @param {String} openTag
+ * @param {String} closeTag
+ */
+function wrapNodeWithHtml(state, node, openTag, closeTag) {
+    state.write(openTag);
+    state.ensureNewLine();
+    state.renderContent(node);
+    state.write(closeTag);
+    state.closeBlock();
+    state.ensureNewLine();
+    state.write('\n');
+}
+
 // Update serializers to just write out as HTML if we have an attribute
 // or element that cannot be represented in commonmark without losing
 // formatting or content.
diff --git a/resources/js/editor/menu/icons.js b/resources/js/editor/menu/icons.js
index 3445ac10d..72a53a5f3 100644
--- a/resources/js/editor/menu/icons.js
+++ b/resources/js/editor/menu/icons.js
@@ -107,6 +107,10 @@ export const icons = {
   iframe: {
     width: 24, height: 24,
     path: "m 22.71,18.43 c 0.03,-0.29 0.04,-0.58 0.01,-0.86 l 1.07,-0.85 c 0.1,-0.08 0.12,-0.21 0.06,-0.32 L 22.82,14.61 C 22.76,14.5 22.63,14.46 22.51,14.5 L 21.23,15 C 21,14.83 20.75,14.69 20.48,14.58 l -0.2,-1.36 C 20.26,13.09 20.16,13 20.03,13 h -2.07 c -0.12,0 -0.23,0.09 -0.25,0.21 l -0.2,1.36 c -0.26,0.11 -0.51,0.26 -0.74,0.42 l -1.28,-0.5 c -0.12,-0.05 -0.25,0 -0.31,0.11 l -1.03,1.79 c -0.06,0.11 -0.04,0.24 0.06,0.32 l 1.07,0.86 c -0.03,0.29 -0.04,0.58 -0.01,0.86 l -1.07,0.85 c -0.1,0.08 -0.12,0.21 -0.06,0.32 l 1.03,1.79 c 0.06,0.11 0.19,0.15 0.31,0.11 L 16.75,21 c 0.23,0.17 0.48,0.31 0.75,0.42 l 0.2,1.36 c 0.02,0.12 0.12,0.21 0.25,0.21 h 2.07 c 0.12,0 0.23,-0.09 0.25,-0.21 l 0.2,-1.36 c 0.26,-0.11 0.51,-0.26 0.74,-0.42 l 1.28,0.5 c 0.12,0.05 0.25,0 0.31,-0.11 l 1.03,-1.79 c 0.06,-0.11 0.04,-0.24 -0.06,-0.32 z M 19,19.5 c -0.83,0 -1.5,-0.67 -1.5,-1.5 0,-0.83 0.67,-1.5 1.5,-1.5 0.83,0 1.5,0.67 1.5,1.5 0,0.83 -0.67,1.5 -1.5,1.5 z M 15,12 9,8 v 8 z M 3,6 h 18 v 5 h 2 V 6 C 23,4.9 22.1,4 21,4 H 3 C 1.9,4 1,4.9 1,6 v 12 c 0,1.1 0.9,2 2,2 h 9 V 18 H 3 Z",
+  },
+  details: {
+    width: 24, height: 24,
+    path: "m 7,10 5,5 5,-5 z M 19,2.5 H 5 c -1.11,0 -2,0.9 -2,2 v 14 c 0,1.1 0.89,2 2,2 h 14 c 1.1,0 2,-0.9 2,-2 v -14 c 0,-1.1 -0.89,-2 -2,-2 z m 0,16 H 5 v -12 h 14 z",
   }
 };
 
diff --git a/resources/js/editor/menu/index.js b/resources/js/editor/menu/index.js
index ecf574642..d88330ab5 100644
--- a/resources/js/editor/menu/index.js
+++ b/resources/js/editor/menu/index.js
@@ -160,7 +160,10 @@ const inserts = [
         new TableCreatorGrid()
     ], {icon: icons.table}),
     itemIframeButton(),
-    itemHtmlSourceButton(),
+    wrapItem(schema.nodes.details, {
+        title: "Dropdown Block",
+        icon: icons.details,
+    })
 ];
 
 const utilities = [
@@ -170,6 +173,7 @@ const utilities = [
         run: removeMarks(),
         enable: state => true,
     }),
+    itemHtmlSourceButton(),
 ];
 
 const menu = menuBar({
diff --git a/resources/js/editor/schema-nodes.js b/resources/js/editor/schema-nodes.js
index 5ebf76a7f..f930d1100 100644
--- a/resources/js/editor/schema-nodes.js
+++ b/resources/js/editor/schema-nodes.js
@@ -1,5 +1,5 @@
 import {orderedList, bulletList, listItem} from "prosemirror-schema-list";
-import {tableNodes} from "prosemirror-tables";
+import {Fragment} from "prosemirror-model";
 
 /**
  * @param {HTMLElement} node
@@ -328,6 +328,35 @@ const table_header = {
     toDOM(node) { return ["th", setCellAttrs(node), 0] }
 };
 
+
+const details = {
+    content: "details_summary block*",
+    isolating: true,
+    group: "block",
+    parseDOM: [{
+        tag: "details",
+        getAttrs(domNode) {
+            return {}
+        },
+    }],
+    toDOM(node) {
+        return ["details",  0];
+    }
+};
+
+const details_summary = {
+    content: "inline*",
+    group: "block",
+    parseDOM: [{
+        tag: "details summary",
+    }],
+    toDOM(node) {
+        return ["summary",  0];
+    }
+};
+
+
+
 const nodes = {
     doc,
     paragraph,
@@ -347,6 +376,8 @@ const nodes = {
     table_row,
     table_cell,
     table_header,
+    details,
+    details_summary,
 };
 
 export default nodes;
\ No newline at end of file
diff --git a/resources/views/editor-test.blade.php b/resources/views/editor-test.blade.php
index ee9537d25..94819121b 100644
--- a/resources/views/editor-test.blade.php
+++ b/resources/views/editor-test.blade.php
@@ -19,6 +19,12 @@
                 Some <a href="https://cats.com" target="_blank" title="link A">Linked Content</a> Lorem ipsum dolor sit amet. <br>
             </p>
 
+            <details>
+                <summary>Dropdown here</summary>
+                <h1>Inner header</h1>
+                <p>Paragraph</p>
+            </details>
+
             <table style="width: 100%;">
                 <thead>
                 <tr>