Hey I have a problem with Firefox Sync. I registered to sync on my workstation. Then I logged into it with my notebook which worked fine but my notebook bookmarks would not appear on my workstation so on my workstation I disconnected from sync and logged in again. Now both devices had the same bookmarks. I then logged into sync on IOS 9.3.1. My IPhone bookmarks would not appear on my notebook so like I did before I disconnected from sync and am now not able to login to it on my notebook anymore. When I type in my e-mail and password it just says "Unexpected Error" when I click on "login" after entering e-mail and password. This is what the console looks like, translated from german: When I open the sync site: 1. Password errors are present on an unsafe (http://) site... When I type in my e-mail and password and click on login: 1. Cross-Origin request blocked: The same rule forbids the reading of external ressources on: https://api.accounts.firefox.com/v1/account/login?keys=true. (Reason: CORS-Preflight-Channel wasn't successful). 2. Unexpected error 74e14951.main.js:18:24077 u<.logError() 74e14951.main.js:18 e() 74e14951.main.js:18 D() 74e14951.main.js:13 s.partial/c() 74e14951.main.js:13 o<._submitForm</<() 74e14951.main.js:25 F() 74e14951.main.js:17 E() 74e14951.main.js:17 l() 74e14951.main.js:17 The latter pointing to the code lines 13, 17, 18 and 25 from this script: https://accounts.firefox.com//scripts/74e14951.main.js I reset Firefox and created a new profile which did not solve the problem. "about:sync-log" is empty. After this didn't work I installed the cors-everywhere addon to get around that cross-origin-request issue. It worked on a test site but not for the sync unfortunately. How to fix this?