diff --git a/.editorconfig b/.editorconfig
index 8963b1270a..580afd5f26 100644
--- a/.editorconfig
+++ b/.editorconfig
@@ -1,6 +1,8 @@
 # Editor configuration normalization
 # https://editorconfig.org/
 
+# See also .github/workflows/editorconfig_conformance.yml
+
 # This is the top-most .editorconfig file; do not search in parent directories.
 root = true
 
@@ -17,3 +19,7 @@ indent_size = 2
 [*.py]
 indent_style = space
 indent_size = 4
+
+[*.yml]
+indent_style = space
+indent_size = 2
diff --git a/.github/workflows/editorconfig_conformance.yml b/.github/workflows/editorconfig_conformance.yml
new file mode 100644
index 0000000000..1f4b0fbd4b
--- /dev/null
+++ b/.github/workflows/editorconfig_conformance.yml
@@ -0,0 +1,35 @@
+name: editorconfig conformance check
+
+on:
+  push:
+    branches:
+      - master
+    paths:
+      - '*.json'
+      - '.github/workflows/editorconfig_conformance.yml'
+  pull_request:
+    branches:
+      - master
+    paths:
+      - '*.json'
+      - '.github/workflows/editorconfig_conformance.yml'
+
+jobs:
+  build:
+    name: CI job
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout Code
+        uses: actions/checkout@v2
+
+      - name: Checkout base_ref
+        run: git fetch --depth=1 origin +${{ github.base_ref }}
+
+      - name: Verify there are no tabs in JSON and py
+        id: build
+        run: |
+          git diff origin/${{ github.base_ref }} --name-only '*.json' '*.py' \
+          | xargs -d'\n' git diff -U0 origin/${{ github.base_ref }} -- \
+          | grep $'^+.*\t' \
+          && exit 1 \
+          || exit 0