Auto merge of #22851 - georgeroman:make_blank_target_imply_noopener, r=cybai,jdm

Make blank target imply noopener, implement "opener" link type

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- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix part of #22845

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components/script/dom/htmlanchorelement.rs

@@ -609,7 +609,14 @@ pub fn follow_hyperlink(subject: &Element, hyperlink_suffix: Option<String>) {
         let values = link_types.Value();
         let contains_noopener = values.contains("noopener");
         let contains_noreferrer = values.contains("noreferrer");
-        contains_noreferrer || contains_noopener
+        let contains_opener = values.contains("opener");
+        let target_is_blank = if let Some(name) = target_attribute_value.as_ref() {
+            name.Value().to_lowercase() == "_blank"
+        } else {
+            false
+        };
+
+        contains_noreferrer || contains_noopener || (!contains_opener && target_is_blank)
     } else {
         false
     };