Notepad++ will do a nice job editing with xml files.
The way I believe it works is ----- (and I keep saying “believe it works”, because I have yet to find any definitive Info from Asobo as to how it is meant to work)
(1) When you start MSFS and it connect to to the MS Severs with your x-box account, it syncs, and makes sure your setting match what is on the server.
(this is why you can delete MSFS from your PC, reload it, and wen you connect, it updates your configuration file on your PC, to what is on your account on the server (YOU HOPE) and does NOT sync and send you an empty Log Book,)
(2) You fly, add to your log book, change settings etc, then close MSFS.
Then when you close MSFS correctly, or at time during MSFS is running, your data is sent back to the MS Servers,
(3) So next time you start MSFS, the process (1) starts again.
There is always a chance, during this close down period, say if you task Kill or Crash, that your data is not sent back to the server.
There is also a chance that data gets corrupted during the sync time.
My Personal solution to help stop loosing data , is to automatically make a copy of all my data, in a date-time named folder, each time BEFORE I start MSFS, (batch file to start MSFS) so I have backups of my configuration and logbook data, every time I have started MSFS,
I hope is IF my MSFS data on my PC or on the server ever gets corrupted, I can FORCE one of my backups back into the Sync process, but so far, I have not had to do this, and so I have not tried –
IF IT AIN’T BROKE, DON’T FIX IT !!!