diff --git a/packages/core/src/helpers/findChildren.ts b/packages/core/src/helpers/findChildren.ts
new file mode 100644
index 00000000..c580ec49
--- /dev/null
+++ b/packages/core/src/helpers/findChildren.ts
@@ -0,0 +1,22 @@
+import { Node as ProseMirrorNode } from 'prosemirror-model'
+import { Predicate } from '../types'
+
+type NodeWithPos = {
+  node: ProseMirrorNode,
+  pos: number,
+}
+
+export default function findChildren(node: ProseMirrorNode, predicate: Predicate): NodeWithPos[] {
+  const nodesWithPos: NodeWithPos[] = []
+
+  node.descendants((child, pos) => {
+    if (predicate(child)) {
+      nodesWithPos.push({
+        node: child,
+        pos,
+      })
+    }
+  })
+
+  return nodesWithPos
+}
diff --git a/packages/core/src/index.ts b/packages/core/src/index.ts
index 78e57616..9e650ac9 100644
--- a/packages/core/src/index.ts
+++ b/packages/core/src/index.ts
@@ -12,6 +12,9 @@ export { default as markPasteRule } from './pasteRules/markPasteRule'
 export { default as callOrReturn } from './utilities/callOrReturn'
 export { default as mergeAttributes } from './utilities/mergeAttributes'
 
+export { default as findChildren } from './helpers/findChildren'
+export { default as findParentNode } from './helpers/findParentNode'
+export { default as findParentNodeClosestToPos } from './helpers/findParentNodeClosestToPos'
 export { default as generateHTML } from './helpers/generateHTML'
 export { default as getSchema } from './helpers/getSchema'
 export { default as getHTMLFromFragment } from './helpers/getHTMLFromFragment'
@@ -22,7 +25,6 @@ export { default as isNodeActive } from './helpers/isNodeActive'
 export { default as isNodeEmpty } from './helpers/isNodeEmpty'
 export { default as isNodeSelection } from './helpers/isNodeSelection'
 export { default as isTextSelection } from './helpers/isTextSelection'
-export { default as findParentNodeClosestToPos } from './helpers/findParentNodeClosestToPos'
 
 export interface Commands {}
 
diff --git a/packages/extension-code-block-lowlight/src/lowlight-plugin.ts b/packages/extension-code-block-lowlight/src/lowlight-plugin.ts
index 30744f1d..84eec5d3 100644
--- a/packages/extension-code-block-lowlight/src/lowlight-plugin.ts
+++ b/packages/extension-code-block-lowlight/src/lowlight-plugin.ts
@@ -2,26 +2,7 @@ import { Plugin, PluginKey } from 'prosemirror-state'
 import { Decoration, DecorationSet } from 'prosemirror-view'
 import { Node as ProsemirrorNode } from 'prosemirror-model'
 import low from 'lowlight/lib/core'
-
-type NodeWithPos = {
-  node: ProsemirrorNode,
-  pos: number,
-}
-
-const findBlockNodes = (doc: ProsemirrorNode) => {
-  const nodes: NodeWithPos[] = []
-
-  doc.descendants((node, pos) => {
-    if (node.isBlock) {
-      nodes.push({
-        node,
-        pos,
-      })
-    }
-  })
-
-  return nodes
-}
+import { findChildren } from '@tiptap/core'
 
 function parseNodes(nodes: any[], className: string[] = []): { text: string, classes: string[] }[] {
   return nodes
@@ -48,8 +29,7 @@ function parseNodes(nodes: any[], className: string[] = []): { text: string, cla
 function getDecorations({ doc, name }: { doc: ProsemirrorNode, name: string}) {
   const decorations: Decoration[] = []
 
-  findBlockNodes(doc)
-    .filter(block => block.node.type.name === name)
+  findChildren(doc, node => node.type.name === name)
     .forEach(block => {
       let startPos = block.pos + 1
       const { language } = block.node.attrs
@@ -88,10 +68,8 @@ export function LowlightPlugin({ name }: { name: string }) {
         // https://discuss.prosemirror.net/t/how-to-update-multiple-inline-decorations-on-node-change/1493
         const oldNodeName = oldState.selection.$head.parent.type.name
         const newNodeName = newState.selection.$head.parent.type.name
-        const oldNodes = findBlockNodes(oldState.doc)
-          .filter(node => node.node.type.name === name)
-        const newNodes = findBlockNodes(newState.doc)
-          .filter(node => node.node.type.name === name)
+        const oldNodes = findChildren(oldState.doc, node => node.type.name === name)
+        const newNodes = findChildren(newState.doc, node => node.type.name === name)
 
         // Apply decorations if selection includes named node, or transaction changes named node.
         if (transaction.docChanged && ([oldNodeName, newNodeName].includes(name)