To everyone using FF 67 stuck with iCloud saying you need to install the add-on: Go into your Firefox App Data directory and open the profiles.ini text file. Then move the line "Default=1" into the section of the profile you are currently using. That fixed it for me.

Will not download bookmarks for Firefox
Installation aborted because the add-on appears to be corrupt.

Like so many others have reported, when I try to enable bookmarks sync using iCloud for Windows, it says I need to install the iCloud Bookmarks add-on for Firefox. But it's already installed and enabled. Looks like i’ll Have to reinstall Chrome :-(

absolutely a pile of shit!

screws up all your bookmarks by putting them all in the same default bookmarks folder along with duplicating them

wtf the going on no update for nearly a year
most reviews are blank whats that all about?

absolutely garbage from apple
they should know better than this

get it sorted guys

have a nice day!

As others have noted, icloud continually tells me i need to download the add--on, even after it's already installed/reinstalled.

When I try to enable bookmarks sync using iCloud for Windows, it says I need to install the iCloud Bookmarks add-on for Firefox. But it's already installed and enabled.

Same issue as other user: When I try to enable bookmarks sync using iCloud for Windows, it says I need to install the iCloud Bookmarks add-on for Firefox. But it's already installed and enabled.

When I try to enable bookmarks sync using iCloud for Windows, it says I need to install the iCloud Bookmarks add-on for Firefox. But it's already installed and enabled.

My iPhone's Safari browser has NEVER stored and bookmarks, even when I tell it to. This extension does nothing to change that; my computer's Firefox bookmarks do not show in my phone's bookmarks, and since the phone's Safari browser refuses to save bookmarks, none are transferred from it to the computer's Firefox, either. Bottom line: This extension does absolutely nothing.

會造成firefox產生無限書籤，每次都要自己手動調整

'' Warning: Do not use alongside Firefox Sync. Causes massive CPU/RAM usage as well as exponential duplication of bookmarks if both are active.''

Isto acima eh verdade, o Mozila precisa corrigir URGENTE esse gravíssimo erro de duplicação de favoritos em vários dispositivos ativos (Sync + icloud) !!!