Recent answers to What is Sync's behavior when logging to a new computer which already has local Firefox data?https://support.mozilla.org/mk/questions/13645572022-01-15T08:14:36-08:00Do you want to remove all data as to Firefox A?
First, shut down the sync account.
Delete Account: L2022-01-15T08:14:36-08:00fredmcd-hotmailhttps://support.mozilla.org/mk/questions/1364557#answer-1474655<p>Do you want to remove all data as to Firefox A?
First, shut down the sync account.
Delete Account: Look for <strong>Delete Account</strong> at the bottom of
<a href="https://accounts.firefox.com/settings" rel="nofollow">https://accounts.firefox.com/settings</a>
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After, create a new sync using the system/profile that has the data.
Wait for a while until the syncing is done before adding any new members.
</p><p>Note: On computer A, I suggest creating a new profile and to sync that.
After, remove the old profile, unless there is something you want in it.
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<p><a href="/en-US/kb/back-and-restore-information-firefox-profiles" rel="nofollow">Back up and restore information in Firefox profiles</a> {web link}
I use a Legacy add-on that makes backups of my user profile, Just In Case&#46;
Unfortunately, it is not compatible with the current Firefox&#46;
</p><p>Every now and then, open the profile folder and create
a <strong>copy</strong> of the current profile <strong>as is</strong> to another location
on your hard drive&#46; This way you will have a backup&#46;
</p><p>If you do this each day, you will not lose much data&#46;
This should be done with <strong>Firefox Closed&#46; </strong>
</p><p>Note: In case you need to restore from these backups,
you may need to overwrite old or corrupted files&#46;
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