Rename Firefox Sync to Mozilla Sync in order to be more inclusive

[data-sync-user]

Recently Thunderbird has started using Sync. There is a proposal put forward for them to rename their service “Thunderbird Sync” (since they’re not Firefox). A follow up comment suggested renaming to “Mozilla Sync”, which is a more inclusive title for the back end service we’re providing.

I think we should consider renaming our service to accommodate the new party.

(Note, we would still require Firefox Accounts (FxA) for authorization, and the client portion would still remain “Firefox Sync”, only the back-end server would be renamed as “Mozilla Sync”)

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