Make no mistake, maintaining synchronization is '''''hard'''''! And this tool is not magic, it does not make the process simple but it ''is'' easier than the alternatives.
<!--
{{man note|Important Note|This tool this requires that the Family Tree being merged must be a Gramps Family Tree ''derived from a version'' of the currently loaded Family Tree.}}
A situation occurs occasionally after giving someone a copy of your tree in our native [[Gramps XML]] format. Then each person makes changes to the copy in their possession using Gramps locally. (You can verify the Trees differ and log those revisions with the [[Addon:Database_Differences_Report|Database Differences]] addon report.)
Programmers call this a 'fork.' (As in: when travelers come to a 'fork in the road' and each chooses different paths.) But the bottom line is that you now have two tree variants derived from a common Tree and you want share your updated Tree. You can't just give the person a fresh copy of your Tree because then their changes would be overwritten.
At some point, you may want to merge the forks into a common tree... without losing the useful changes from either tree. That synchronization is what this tool is designed to facilitate. It depends on the two Trees sharing common internal handles (not just the user-editable IDs) to simplify ignoring unchanged records. Then the tool focuses you on just the changes.
But say the other user doesn't use Gramps, so you exported with [[Gramps_and_GEDCOM|GEDCOM]] (or another format) and got it back? Sorry... this tool won't be any easier than a manual merge after a standard import. You'd still need to hand compare every record.
The derived trees need not be limited to those edited by someone else. I often take a copy of my tree on my laptop when traveling and sometimes I make updates while on the road. But then I may forget to copy it back to my home desktop computer until after I've made more updates. This tool helps to merge these back together.
{{man warn|1=Warning: Data Corruption Risk |2=Mass changes mean more potential for mangling the data. Back up your current tree BEFORE using this tool to merge.<br />If something goes wrong, you will have a way to go back and start over. See [[How to make a backup|make a Gramps XML backup]].}}
-->
==Installation==
The addon requires a Gramps Web account with owner privileges, Gramps 5.1 running on Python 3.7 or newer.