diff --git a/features/case-insensitive-attributes.yml b/features/case-insensitive-attributes.yml
new file mode 100644
index 00000000000..32281aa8ced
--- /dev/null
+++ b/features/case-insensitive-attributes.yml
@@ -0,0 +1,7 @@
+name: Case-insensitive attribute selector
+description: The `i` identifier in a CSS attribute selector matches attribute values case-insensitively in document languages like XML where attribute values are case-sensitive.
+spec: https://drafts.csswg.org/selectors-4/#attribute-case
+caniuse: css-case-insensitive
+group: selectors
+compat_features:
+  - css.selectors.attribute.case_insensitive_modifier
diff --git a/features/case-insensitive-attributes.yml.dist b/features/case-insensitive-attributes.yml.dist
new file mode 100644
index 00000000000..b7552eb329c
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+++ b/features/case-insensitive-attributes.yml.dist
@@ -0,0 +1,17 @@
+# Generated from: case-insensitive-attributes.yml
+# Do not edit this file by hand. Edit the source file instead!
+
+status:
+  baseline: high
+  baseline_low_date: 2020-01-15
+  baseline_high_date: 2022-07-15
+  support:
+    chrome: "49"
+    chrome_android: "49"
+    edge: "79"
+    firefox: "47"
+    firefox_android: "47"
+    safari: "9"
+    safari_ios: "9"
+compat_features:
+  - css.selectors.attribute.case_insensitive_modifier
diff --git a/features/case-sensitive-attributes.yml b/features/case-sensitive-attributes.yml
new file mode 100644
index 00000000000..00a92020db4
--- /dev/null
+++ b/features/case-sensitive-attributes.yml
@@ -0,0 +1,6 @@
+name: Case-sensitive attribute selector
+description: The `s` identifier in a CSS attribute selector matches attribute values case-sensitively in document languages like HTML where attribute values are case-insensitive.
+spec: https://drafts.csswg.org/selectors-4/#attribute-case
+group: selectors
+compat_features:
+  - css.selectors.attribute.case_sensitive_modifier
diff --git a/features/case-sensitive-attributes.yml.dist b/features/case-sensitive-attributes.yml.dist
new file mode 100644
index 00000000000..121c3b4edab
--- /dev/null
+++ b/features/case-sensitive-attributes.yml.dist
@@ -0,0 +1,10 @@
+# Generated from: case-sensitive-attributes.yml
+# Do not edit this file by hand. Edit the source file instead!
+
+status:
+  baseline: false
+  support:
+    firefox: "66"
+    firefox_android: "66"
+compat_features:
+  - css.selectors.attribute.case_sensitive_modifier
diff --git a/features/open-closed.yml b/features/open-closed.yml
new file mode 100644
index 00000000000..9e6c464a0b3
--- /dev/null
+++ b/features/open-closed.yml
@@ -0,0 +1,7 @@
+name: Open and closed selectors
+description: The `:open` and `:closed` CSS pseudo-classes match elements that have open and closed states, like `<details`, `<dialog>`, or `<select>`, based on their state.
+spec: https://drafts.csswg.org/selectors-4/#open-state
+group: selectors
+compat_features:
+  - css.selectors.closed
+  - css.selectors.open
diff --git a/features/open-closed.yml.dist b/features/open-closed.yml.dist
new file mode 100644
index 00000000000..966d7745a7b
--- /dev/null
+++ b/features/open-closed.yml.dist
@@ -0,0 +1,9 @@
+# Generated from: open-closed.yml
+# Do not edit this file by hand. Edit the source file instead!
+
+status:
+  baseline: false
+  support: {}
+compat_features:
+  - css.selectors.closed
+  - css.selectors.open
diff --git a/features/target-within.yml b/features/target-within.yml
new file mode 100644
index 00000000000..eef65394b69
--- /dev/null
+++ b/features/target-within.yml
@@ -0,0 +1,6 @@
+name: :target-within
+description: The `:target-within` CSS pseudo-class matches the element with an ID matching the URL fragment and its ancestors.
+spec: https://drafts.csswg.org/selectors-4/#the-target-within-pseudo
+group: selectors
+compat_features:
+  - css.selectors.target-within
diff --git a/features/target-within.yml.dist b/features/target-within.yml.dist
new file mode 100644
index 00000000000..16a54b67d7f
--- /dev/null
+++ b/features/target-within.yml.dist
@@ -0,0 +1,8 @@
+# Generated from: target-within.yml
+# Do not edit this file by hand. Edit the source file instead!
+
+status:
+  baseline: false
+  support: {}
+compat_features:
+  - css.selectors.target-within
diff --git a/features/time-relative-selectors.yml b/features/time-relative-selectors.yml
new file mode 100644
index 00000000000..37a2725e86b
--- /dev/null
+++ b/features/time-relative-selectors.yml
@@ -0,0 +1,8 @@
+name: Time-relative pseudo-selectors
+description: The `:future` and `:past` CSS pseudo-classes match upcoming or prior elements during media playback.
+spec: https://drafts.csswg.org/selectors-4/#time-pseudos
+group: selectors
+compat_features:
+  - css.selectors.future
+  - css.selectors.past
+  # Note: `:current` has no support anywhere yet.
diff --git a/features/time-relative-selectors.yml.dist b/features/time-relative-selectors.yml.dist
new file mode 100644
index 00000000000..3c8f9733b9c
--- /dev/null
+++ b/features/time-relative-selectors.yml.dist
@@ -0,0 +1,14 @@
+# Generated from: time-relative-selectors.yml
+# Do not edit this file by hand. Edit the source file instead!
+
+status:
+  baseline: false
+  support:
+    chrome: "23"
+    chrome_android: "25"
+    edge: "79"
+    safari: "7"
+    safari_ios: "7"
+compat_features:
+  - css.selectors.future
+  - css.selectors.past