Sync will not stay disabled

[adisib]

I don't use the sync service, so I had set services.sync.enabled to false in about:config. One day when looking in about:config, I noticed that it was enabled. I wondered why, then disabled it, restarting the browser, and it stayed disabled as it should. Today I checked again, and sync has enabled itself again. I can't find a specific cause, but it has certainly re-enabled it several times now without me knowing until I've checked.

If I don't use sync, I should be able to disable it and have it stay that way.