Google-chrome – Google Chrome Extensions are not Syncing

I'm not sure about Chrome's internal sync, but you might try XMarks sync. It offers sync between browsers as well as computers across the internet. It supports all 4 major browsers. You can also access your bookmarks from any computer via their web portal, in case you find yourself on another computer and need access to your bookmarks. And if you upgrade to their pay service, you can sync to your iPhone, Blackberry or Android device as well and gain access to their open tab sync, where you can close your browser on one computer, go to another computer, open up the browser and all the tabs you had open will be opened on the new computer.

You can type chrome://sync-internals in the omnibox. It lets you view internal and technical data about your connection to the Google Cloud. It is actually intended for developers, but it can also be used to know the status of the sync.

In the About tab, you can find "Last Synced", if it shows "Just Now" you can be sure that the sync process completed just now, and be sure that everything has been synced.
There is one more field "Syncing" which shows the status of sync, if its true it means the syns is being done and you should wait.

You can experiment with it by adding/removing a bookmark and observe the changes on the page, this way you will be able to better understand the status of the sync and information displayed at page.

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