We need to look at the sync logs. Type about:sync-log<enter> in the address bar.

Open the last file created and Copy its contents Now Paste it into this forum.

If the file is too large;

Open a text / word program and load the file. Left-click once. Now <Control> A to highlight everything, then <Control> C to copy it.

Next, have your web browser go to; https://pastebin.com/

Paste <Control> P the content of the file in the window. Note: On the bottom, fill out the boxes as best you can.

Now press Create A New Paste. The page will reload. Copy the new web address, and post it here.

You can find my latest sync log here : https://pastebin.com/zNBthYNG

When I look with about:sync (an extension), I can see that there is only four? extensions in my sync account, all added after the initial sync.

Client Records lists all my extensions

I called for more help.

Type about:accounts<enter> in the address bar. [57+] https://accounts.firefox.com/settings

Make sure everything you want to sync is selected.

Please list the Firefox versions that are on the sync. Note that some things may not be compatible between different versions.

I'm an IT guy, so all this basic stuff I already checked. They are the firsts results from Google.

Anyway,

My firefoxes are all updated. I have 65.0.1 (waiting to restart) on the initial machine. Same on the laptop. (edit : I restarted my firefox, and now the version is 65.0.2)

As for the sync options, everything is checked.

edit : After updating, I forced a Sync (with the sync button), and looking with about:sync, I can now see my extensions. They are now correctly syncing.