deleted file mode 100644
--- a/testing/web-platform/meta/html/browsers/the-window-object/historical.window.js.ini
+++ /dev/null
@@ -1,15 +0,0 @@
-[historical.window.html]
-  type: testharness
-  [showModalDialog() has been removed from the platform]
-    expected:
-      if debug and not e10s and (os == "linux") and (version == "Ubuntu 16.04") and (processor == "x86") and (bits == 32): FAIL
-      if not debug and not e10s and (os == "linux") and (version == "Ubuntu 16.04") and (processor == "x86_64") and (bits == 64): FAIL
-      if debug and not e10s and (os == "win") and (version == "6.1.7601") and (processor == "x86") and (bits == 32): FAIL
-      if not debug and not e10s and (os == "linux") and (version == "Ubuntu 16.04") and (processor == "x86") and (bits == 32): FAIL
-      if not debug and not e10s and (os == "win") and (version == "6.1.7601") and (processor == "x86") and (bits == 32): FAIL
-      if not debug and not e10s and (os == "win") and (version == "6.2.9200") and (processor == "x86_64") and (bits == 64): FAIL
-      if debug and not e10s and (os == "win") and (version == "6.2.9200") and (processor == "x86_64") and (bits == 64): FAIL
-      if debug and not e10s and (os == "linux") and (version == "Ubuntu 16.04") and (processor == "x86_64") and (bits == 64): FAIL
-      if not debug and not e10s and (os == "mac") and (version == "OS X 10.10.5") and (processor == "x86_64") and (bits == 64): FAIL
-      if not debug and not e10s and (os == "win") and (version == "10.0.15063") and (processor == "x86_64") and (bits == 64): FAIL
-

--- a/testing/web-platform/meta/html/browsers/the-window-object/security-window/window-security.html.ini
+++ b/testing/web-platform/meta/html/browsers/the-window-object/security-window/window-security.html.ini
@@ -3,13 +3,8 @@
   [A SecurityError exception must be thrown when window.oncancel is accessed from a different origin.]
     expected: FAIL
 
   [A SecurityError exception must be thrown when window.oncuechange is accessed from a different origin.]
     expected: FAIL
 
   [A SecurityError exception must be thrown when window.onmousewheel is accessed from a different origin.]
     expected: FAIL
-
-  [A SecurityError exception must be thrown when window.showModalDialog is accessed from a different origin.]
-    disabled:
-      if e10s: https://bugzilla.mozilla.org/show_bug.cgi?id=981796
-

--- a/testing/web-platform/meta/html/dom/interfaces.html.ini
+++ b/testing/web-platform/meta/html/dom/interfaces.html.ini
@@ -1508,55 +1508,43 @@
     expected: FAIL
 
   [Path2D interface: operation addPathByStrokingText(DOMString,CanvasDrawingStyles,SVGMatrix,Path2D,unrestricted double)]
     expected: FAIL
 
   [DataTransfer interface object length]
     expected: FAIL
 
-  [Window interface: operation showModalDialog(DOMString,any)]
-    disabled:
-      if e10s: https://bugzilla.mozilla.org/show_bug.cgi?id=981796
-
   [Window interface: attribute oncancel]
     expected: FAIL
 
   [Window interface: attribute oncuechange]
     expected: FAIL
 
   [Window interface: attribute onmousewheel]
     expected: FAIL
 
   [Window interface: attribute onsort]
     expected: FAIL
 
   [Window interface: operation createImageBitmap(ImageBitmapSource,long,long,long,long)]
     expected: FAIL
 
-  [Window interface: window must inherit property "showModalDialog" with the proper type (34)]
-    disabled:
-      if e10s: https://bugzilla.mozilla.org/show_bug.cgi?id=981796
-
   [Window interface: window must inherit property "oncancel" with the proper type (42)]
     expected: FAIL
 
   [Window interface: window must inherit property "oncuechange" with the proper type (49)]
     expected: FAIL
 
   [Window interface: window must inherit property "onmousewheel" with the proper type (80)]
     expected: FAIL
 
   [Window interface: window must inherit property "onsort" with the proper type (93)]
     expected: FAIL
 
-  [Window interface: calling showModalDialog(DOMString,any) on window with too few arguments must throw TypeError]
-    disabled:
-      if e10s: https://bugzilla.mozilla.org/show_bug.cgi?id=981796
-
   [Window interface: calling createImageBitmap(ImageBitmapSource,long,long,long,long) on window with too few arguments must throw TypeError]
     expected: FAIL
 
   [Location interface: operation assign(DOMString)]
     expected: FAIL
 
   [Location interface: operation replace(DOMString)]
     expected: FAIL