diff --git a/dom/websocket/WebSocket.cpp b/dom/websocket/WebSocket.cpp
index 3ea2b63f5f678..bac4cb734353a 100644
--- a/dom/websocket/WebSocket.cpp
+++ b/dom/websocket/WebSocket.cpp
@@ -552,6 +552,13 @@ nsIWebSocketImpl
 h
 "
 #
+include
+"
+nsIURIMutator
+.
+h
+"
+#
 define
 OPEN_EVENT_STRING
 u
@@ -887,6 +894,9 @@ const
 nsAString
 &
 aURL
+nsIURI
+*
+aBaseURI
 )
 ;
 nsresult
@@ -4733,6 +4743,17 @@ return
 true
 ;
 }
+nsIPrincipal
+*
+principal
+=
+mWorkerPrivate
+-
+>
+GetPrincipal
+(
+)
+;
 mErrorCode
 =
 mImpl
@@ -4745,12 +4766,7 @@ jsapi
 cx
 (
 )
-mWorkerPrivate
--
->
-GetPrincipal
-(
-)
+principal
 -
 >
 SchemeIs
@@ -4759,12 +4775,7 @@ SchemeIs
 https
 "
 )
-doc
--
->
-NodePrincipal
-(
-)
+principal
 mClientInfo
 mWorkerPrivate
 -
@@ -7217,11 +7228,25 @@ IsSystemPrincipal
 (
 )
 ;
+nsCOMPtr
+<
+nsIURI
+>
+baseURI
+=
+aPrincipal
+-
+>
+GetURI
+(
+)
+;
 rv
 =
 ParseURL
 (
 aURL
+baseURI
 )
 ;
 NS_ENSURE_SUCCESS
@@ -9239,6 +9264,9 @@ const
 nsAString
 &
 aURL
+nsIURI
+*
+aBaseURI
 )
 {
 AssertIsOnMainThread
@@ -9297,6 +9325,8 @@ getter_AddRefs
 uri
 )
 aURL
+nullptr
+aBaseURI
 )
 ;
 NS_ENSURE_SUCCESS
@@ -9324,18 +9354,17 @@ rv
 NS_ERROR_DOM_SYNTAX_ERR
 )
 ;
-bool
-hasRef
+nsAutoCString
+scheme
 ;
 rv
 =
 parsedURL
 -
 >
-GetHasRef
+GetScheme
 (
-&
-hasRef
+scheme
 )
 ;
 NS_ENSURE_TRUE
@@ -9347,21 +9376,92 @@ rv
 &
 &
 !
-hasRef
+scheme
+.
+IsEmpty
+(
+)
 NS_ERROR_DOM_SYNTAX_ERR
 )
 ;
-nsAutoCString
+if
+(
 scheme
+=
+=
+"
+http
+"
+|
+|
+scheme
+=
+=
+"
+https
+"
+)
+{
+scheme
+=
+scheme
+=
+=
+"
+https
+"
+?
+"
+wss
+"
+_ns
+:
+"
+ws
+"
+_ns
+;
+NS_MutateURI
+mutator
+(
+parsedURL
+)
+;
+mutator
+.
+SetScheme
+(
+scheme
+)
+;
+rv
+=
+mutator
+.
+Finalize
+(
+parsedURL
+)
+;
+NS_ENSURE_SUCCESS
+(
+rv
+NS_ERROR_DOM_SYNTAX_ERR
+)
+;
+}
+bool
+hasRef
 ;
 rv
 =
 parsedURL
 -
 >
-GetScheme
+GetHasRef
 (
-scheme
+&
+hasRef
 )
 ;
 NS_ENSURE_TRUE
@@ -9373,11 +9473,7 @@ rv
 &
 &
 !
-scheme
-.
-IsEmpty
-(
-)
+hasRef
 NS_ERROR_DOM_SYNTAX_ERR
 )
 ;
diff --git a/dom/websocket/tests/file_websocket_wsh.py b/dom/websocket/tests/file_websocket_wsh.py
index b9cad72c0bc76..35b44144c5a91 100644
--- a/dom/websocket/tests/file_websocket_wsh.py
+++ b/dom/websocket/tests/file_websocket_wsh.py
@@ -278,6 +278,48 @@
 "
 test
 -
+1
+"
+or
+request
+.
+ws_protocol
+=
+=
+"
+test
+-
+4
+"
+:
+        
+msgutil
+.
+send_message
+(
+request
+"
+server
+data
+"
+)
+        
+msgutil
+.
+close_connection
+(
+request
+)
+    
+elif
+request
+.
+ws_protocol
+=
+=
+"
+test
+-
 2
 .
 1
diff --git a/dom/websocket/tests/websocket_tests.js b/dom/websocket/tests/websocket_tests.js
index 694f5fefa5b90..04c415a60a517 100644
--- a/dom/websocket/tests/websocket_tests.js
+++ b/dom/websocket/tests/websocket_tests.js
@@ -13,8 +13,6 @@ resolve
 reject
 )
 {
-try
-{
 var
 ws
 =
@@ -41,38 +39,56 @@ tests
 /
 file_websocket
 "
+"
+test
+-
+1
+"
 )
 ;
+ws
+.
+onmessage
+=
+function
+(
+)
+{
 ok
 (
-false
+true
 "
-test1
-failed
+created
+websocket
+with
+http
+scheme
 "
 )
 ;
 }
-catch
+;
+ws
+.
+onclose
+=
+function
 (
 e
 )
 {
-ok
+shouldCloseCleanly
 (
-true
-"
-test1
-failed
-"
+e
 )
 ;
-}
 resolve
 (
 )
 ;
 }
+;
+}
 )
 ;
 }
@@ -449,8 +465,6 @@ resolve
 reject
 )
 {
-try
-{
 var
 ws
 =
@@ -459,42 +473,56 @@ CreateTestWS
 "
 file_websocket
 "
-)
-;
-ok
-(
-false
 "
 test
 -
 4
-failed
 "
 )
 ;
-}
-catch
+ws
+.
+onmessage
+=
+function
 (
-e
 )
 {
 ok
 (
 true
 "
-test
--
-4
-failed
+created
+websocket
+with
+relative
+scheme
 "
 )
 ;
 }
+;
+ws
+.
+onclose
+=
+function
+(
+e
+)
+{
+shouldCloseCleanly
+(
+e
+)
+;
 resolve
 (
 )
 ;
 }
+;
+}
 )
 ;
 }
diff --git a/testing/web-platform/meta/websockets/Create-http-urls.any.js.ini b/testing/web-platform/meta/websockets/Create-http-urls.any.js.ini
deleted file mode 100644
index 8c0c227fd5b85..0000000000000
--- a/testing/web-platform/meta/websockets/Create-http-urls.any.js.ini
+++ /dev/null
@@ -1,50 +0,0 @@
-[
-Create
--
-http
--
-urls
-.
-any
-.
-worker
-.
-html
-]
-[
-WebSocket
-:
-ensure
-both
-HTTP
-schemes
-are
-supported
-]
-expected
-:
-FAIL
-[
-Create
--
-http
--
-urls
-.
-any
-.
-html
-]
-[
-WebSocket
-:
-ensure
-both
-HTTP
-schemes
-are
-supported
-]
-expected
-:
-FAIL
diff --git a/testing/web-platform/meta/websockets/Create-invalid-urls.any.js.ini b/testing/web-platform/meta/websockets/Create-invalid-urls.any.js.ini
deleted file mode 100644
index bbcb29765eff5..0000000000000
--- a/testing/web-platform/meta/websockets/Create-invalid-urls.any.js.ini
+++ /dev/null
@@ -1,192 +0,0 @@
-[
-Create
--
-invalid
--
-urls
-.
-any
-.
-worker
-.
-html
-?
-wpt_flags
-=
-h2
-]
-expected
-:
-if
-(
-os
-=
-=
-"
-android
-"
-)
-and
-fission
-:
-[
-OK
-TIMEOUT
-]
-[
-Create
--
-invalid
--
-urls
-.
-any
-.
-html
-]
-expected
-:
-if
-(
-os
-=
-=
-"
-android
-"
-)
-and
-fission
-:
-[
-OK
-TIMEOUT
-]
-[
-Create
--
-invalid
--
-urls
-.
-any
-.
-html
-?
-wss
-]
-expected
-:
-if
-(
-os
-=
-=
-"
-android
-"
-)
-and
-fission
-:
-[
-OK
-TIMEOUT
-]
-[
-Create
--
-invalid
--
-urls
-.
-any
-.
-worker
-.
-html
-?
-wss
-]
-expected
-:
-if
-(
-os
-=
-=
-"
-android
-"
-)
-and
-fission
-:
-[
-OK
-TIMEOUT
-]
-[
-Create
--
-invalid
--
-urls
-.
-any
-.
-worker
-.
-html
-]
-expected
-:
-if
-(
-os
-=
-=
-"
-android
-"
-)
-and
-fission
-:
-[
-OK
-TIMEOUT
-]
-[
-Create
--
-invalid
--
-urls
-.
-any
-.
-html
-?
-wpt_flags
-=
-h2
-]
-expected
-:
-if
-(
-os
-=
-=
-"
-android
-"
-)
-and
-fission
-:
-[
-OK
-TIMEOUT
-]
diff --git a/testing/web-platform/meta/websockets/Create-non-absolute-url.any.js.ini b/testing/web-platform/meta/websockets/Create-non-absolute-url.any.js.ini
deleted file mode 100644
index bf5c25ad674fd..0000000000000
--- a/testing/web-platform/meta/websockets/Create-non-absolute-url.any.js.ini
+++ /dev/null
@@ -1,324 +0,0 @@
-[
-Create
--
-non
--
-absolute
--
-url
-.
-any
-.
-html
-]
-expected
-:
-if
-(
-os
-=
-=
-"
-android
-"
-)
-and
-fission
-:
-[
-OK
-TIMEOUT
-]
-[
-Create
-WebSocket
--
-Pass
-a
-non
-absolute
-URL
-:
-test
-]
-expected
-:
-FAIL
-[
-Create
-WebSocket
--
-Pass
-a
-non
-absolute
-URL
-:
-?
-]
-expected
-:
-FAIL
-[
-Create
-WebSocket
--
-Pass
-a
-non
-absolute
-URL
-:
-null
-]
-expected
-:
-FAIL
-[
-Create
-WebSocket
--
-Pass
-a
-non
-absolute
-URL
-:
-123
-]
-expected
-:
-FAIL
-[
-Create
--
-non
--
-absolute
--
-url
-.
-any
-.
-html
-?
-wpt_flags
-=
-h2
-]
-expected
-:
-if
-(
-os
-=
-=
-"
-android
-"
-)
-and
-fission
-:
-[
-OK
-TIMEOUT
-]
-[
-Create
--
-non
--
-absolute
--
-url
-.
-any
-.
-html
-?
-wss
-]
-expected
-:
-if
-(
-os
-=
-=
-"
-android
-"
-)
-and
-fission
-:
-[
-OK
-TIMEOUT
-]
-[
-Create
--
-non
--
-absolute
--
-url
-.
-any
-.
-worker
-.
-html
-?
-wpt_flags
-=
-h2
-]
-expected
-:
-if
-(
-os
-=
-=
-"
-android
-"
-)
-and
-fission
-:
-[
-OK
-TIMEOUT
-]
-[
-Create
--
-non
--
-absolute
--
-url
-.
-any
-.
-worker
-.
-html
-?
-wss
-]
-expected
-:
-if
-(
-os
-=
-=
-"
-android
-"
-)
-and
-fission
-:
-[
-OK
-TIMEOUT
-]
-[
-Create
--
-non
--
-absolute
--
-url
-.
-any
-.
-worker
-.
-html
-]
-expected
-:
-if
-(
-os
-=
-=
-"
-android
-"
-)
-and
-fission
-:
-[
-OK
-TIMEOUT
-]
-[
-Create
-WebSocket
--
-Pass
-a
-non
-absolute
-URL
-:
-test
-]
-expected
-:
-FAIL
-[
-Create
-WebSocket
--
-Pass
-a
-non
-absolute
-URL
-:
-?
-]
-expected
-:
-FAIL
-[
-Create
-WebSocket
--
-Pass
-a
-non
-absolute
-URL
-:
-null
-]
-expected
-:
-FAIL
-[
-Create
-WebSocket
--
-Pass
-a
-non
-absolute
-URL
-:
-123
-]
-expected
-:
-FAIL
diff --git a/testing/web-platform/meta/websockets/Create-url-with-windows-1252-encoding.html.ini b/testing/web-platform/meta/websockets/Create-url-with-windows-1252-encoding.html.ini
deleted file mode 100644
index 227c8d578dd52..0000000000000
--- a/testing/web-platform/meta/websockets/Create-url-with-windows-1252-encoding.html.ini
+++ /dev/null
@@ -1,34 +0,0 @@
-[
-Create
--
-url
--
-with
--
-windows
--
-1252
--
-encoding
-.
-html
-]
-[
-URL
-'
-s
-percent
--
-encoding
-is
-always
-in
-UTF
--
-8
-for
-WebSocket
-]
-expected
-:
-FAIL
diff --git a/testing/web-platform/meta/websockets/multi-globals/url-parsing/url-parsing.html.ini b/testing/web-platform/meta/websockets/multi-globals/url-parsing/url-parsing.html.ini
deleted file mode 100644
index 3c76263a29378..0000000000000
--- a/testing/web-platform/meta/websockets/multi-globals/url-parsing/url-parsing.html.ini
+++ /dev/null
@@ -1,20 +0,0 @@
-[
-url
--
-parsing
-.
-html
-]
-[
-Multiple
-globals
-for
-base
-URL
-in
-WebSocket
-constructor
-]
-expected
-:
-FAIL