this stopped working ages ago and now i can't sync anything because the addons for pc don't work.. 100% useless

If you're having trouble with Bookmark synchronisation uninstall iCloud for Windows and reinstall the lastest version from the Windows Store. I was having the same issue because I was using an outdated version. Working flawlessly after that.

同步的数据乱七八糟，重复太多了，删除了重复的后面又出现了很多重复的书签！