Bug 1456807 - Disable browser_taskbar_preview.js for frequent failures. r=jmaher

browser/modules/test/browser/browser.ini

@@ -33,7 +33,7 @@ skip-if = !e10s
 [browser_SitePermissions_expiry.js]
 [browser_SitePermissions_tab_urls.js]
 [browser_taskbar_preview.js]
-skip-if = os != "win"
+skip-if = os != win || (os == win && bits == 64) # bug 1456807
 [browser_UnsubmittedCrashHandler.js]
 run-if = crashreporter
 [browser_urlBar_zoom.js]