Bug 1809430 - Minor follow-up test fixes and tweaks.

The scroll restoration is only needed with socket process for some
reason, but I can't make the test pass locally even before my changes.

MANUAL PUSH: Orange fix CLOSED TREE

toolkit/content/tests/browser/browser_findbar_marks.js

@@ -188,7 +188,7 @@ add_task(async function test_found_resize() {
     "resize",
     true
   );
-  window2.resizeTo(outerWidth - 100, outerHeight - 80);
+  window2.resizeTo(window2.outerWidth - 100, window2.outerHeight - 80);
   await resizePromise;
 
   // Some number of extra scrollbar adjustment and painting events can occur

toolkit/mozapps/extensions/test/browser/browser_html_scroll_restoration.js

@@ -124,8 +124,9 @@ function assertNonZeroScrollOffsets(offsets) {
 
 function checkScrollOffset(win, expected, msg = "") {
   let actual = getScrollOffset(win);
-  isfuzzy(actual.top, expected.top, 1, `Top scroll offset - ${msg}`);
-  isfuzzy(actual.left, expected.left, 1, `Left scroll offset - ${msg}`);
+  let fuzz = AppConstants.platform == "macosx" ? 3 : 1;
+  isfuzzy(actual.top, expected.top, fuzz, `Top scroll offset - ${msg}`);
+  isfuzzy(actual.left, expected.left, fuzz, `Left scroll offset - ${msg}`);
 }
 
 add_task(async function test_scroll_restoration() {