Ok lets try this

.github/workflows/sync-to-readthedocs-repo.yaml

@@ -0,0 +1,72 @@
+name: "sync-to-readthedocs-repo"
+
+on:
+  workflow_dispatch:
+  push:
+    branches:
+      - main
+      - latest
+      - develop
+      - 'pre/*'
+      - 'demo/test/*'
+    tags:
+      - 'v*'
+      - 'demo/*'
+
+jobs:
+  extract_branch_or_tag:
+    outputs:
+      ref_name: ${{ steps.extract.outputs.ref_name }}
+    runs-on: ubuntu-latest
+    steps:
+      - id: extract
+        name: Extract branch or tag name
+        shell: bash
+        run: |
+          REF_NAME="${GITHUB_REF#refs/*/}"
+          echo "::set-output name=ref_name::$REF_NAME"
+          echo "Extracted ref: $REF_NAME"
+
+  build-and-deploy:
+    permissions:
+      contents: write
+    needs: extract_branch_or_tag
+    runs-on: ubuntu-latest
+    steps:
+      # Conditional Checkout for Branch
+      - name: Checkout Branch if branch-triggered-sync
+        if: contains(github.ref, 'refs/heads/')
+        uses: actions/checkout@v3
+        with:
+          submodules: true
+          token: ${{ secrets.GH_PAT }}
+          ref: ${{ needs.extract_branch_or_tag.outputs.ref_name }}
+
+      - name: Push corresponding reference to mirror repo if a branch
+        if: contains(github.ref, 'refs/heads/')
+        run: |
+          git fetch --unshallow origin ${{ needs.extract_branch_or_tag.outputs.ref_name }}
+          git pull origin ${{ needs.extract_branch_or_tag.outputs.ref_name }}
+          git remote add mirror https://github.com/flexcompute-readthedocs/tidy3d-notebook-docs.git
+          git push mirror ${{ needs.extract_branch_or_tag.outputs.ref_name }} --force # overwrites always
+        env:
+          GITHUB_TOKEN: ${{ secrets.GH_PAT }}
+
+      # Conditional Checkout for Tag
+      - name: Checkout Tag if tag-triggered-sync
+        if: contains(github.ref, 'refs/tags/')
+        uses: actions/checkout@v3
+        with:
+          submodules: true
+          token: ${{ secrets.GH_PAT }}
+          fetch-depth: 0
+          ref: ${{ needs.extract_branch_or_tag.outputs.ref_name }}
+          fetch-tags: true
+
+      - name: Push corresponding reference to mirror repo if a tag
+        if: contains(github.ref, 'refs/tags/')
+        run: |
+          git remote add mirror https://github.com/flexcompute-readthedocs/tidy3d-notebook-docs.git
+          git push mirror ${{ needs.extract_branch_or_tag.outputs.ref_name }} --force # overwrites always
+        env:
+          GITHUB_TOKEN: ${{ secrets.GH_PAT }}

.readthedocs.yaml

@@ -1,25 +1,19 @@
 version: 2
-
-submodules:
-  include:
-    - tidy3d
-  recursive: true
-
 build:
-  os: "ubuntu-20.04"
+  os: "ubuntu-22.04"
   tools:
-    python: "3.10"
+    python: "3.11"
 sphinx:
   fail_on_warning: false
-  configuration: docs/source/conf.py
+  configuration: docs/conf.py
 
 python:
   # Install our python package before building the docs
   install:
     - method: pip
       path: .
-    - requirements: docs/requirements.txt
-    - requirements: tidy3d/requirements.txt
+      extra_requirements:
+        - dev
 
 formats: []
 

docs/conf.py

@@ -0,0 +1,4 @@
+from ...conf import *
+
+extensions = extensions
+project = "Tidy3D Examples"