There are 2 processes involved in Firefox Sync, and 0 differentiation between them in the language used to describe what Firefox Sync does in any of the documentation, th… (read more)
There are 2 processes involved in Firefox Sync, and 0 differentiation between them in the language used to describe what Firefox Sync does in any of the documentation, this makes nearly every discussion on the topic highly confusing to borderline misleading.
When you press Sync, you are pushing settings to Firefox servers.
When you sign in to Sync, you are pulling settings from Firefox servers.
Both of these steps are referred to interchangeably as "syncing" and there is next to no documentation of what causes each to occur nor what they actually do.
Why is this dangerous you might ask?
Well, let's say I buy a new computer, I want to set it up the same way I use all my devices, so I sign in to sync to synchronize my settings, makes perfect sense. Nothing tells me anything is happening when I sign in, so I click the sync button because I want to synchronize my settings with my other devices.
I've just overwritten the server-side sync profile with a default Firefox profile.
You know how you fix that?
You sign in and press the sync button to overwrite the sync profile again.
But you know what happens when you sign in? You become synced with the now blank sync profile and lose all the settings that you want to be pushing to the sync profile.
This just happened to me.
Thankfully I was only choosing to sync add-ons and options AT THE TIME and I have backups that are about 6 months old and I rarely change settings, but some things like my homepage URLs are something that I do change fairly often, and I'm sure some additional sites were whitelisted since by default I just reject all cookies. I also thankfully use policies.json to block updates so I didn't immediately get assaulted by that too.
SO! I HIGHLY suggest that when merely signing in to Sync, the default should be for syncing to be off to start off with, so that you can choose what to "sync" BEFORE it occurs.
However, because of the language, the question arises, what am I choosing to sync for? Am I choosing what to PULL from servers? Or am I choosing what gets PUSHED to the servers? When syncing is turned on, does that mean I an pulling the settings that I have chosen? Or am I am pulling ALL settings while only pushing what I have chosen IF I click the Sync button? Or do I push EVERYTHING?
It's incredibly unclear how the Sync feature works and both of the "main" articles on it are completely useless for understanding it because the term "sync" is used interchangeably for pushing or pulling settings.
What are the correct steps to rectify this horrid situation? Sign-in, set-up sync, choose "Options" and "Add-Ons" again, THEN copy over the backup settings, THEN Sync them to the "cloud"?
If I have 2 different devices setup with sync, and 1 chooses to sync options and the other chooses to sync bookmarks, then I click sync on BOTH devices repeatedly, what occurs?