Syncing between version 2.10.2 and 2.11.2 does not work

I was travelling with my Macbook Air (El Capitain) and wrote a lot in DevonThink 2.10.2, expecting it to sync as it used to do with my iMac (Sierra) after my return. However, my DevonThink app there is version 2.11.2, and no matter how often I click on “Synchronize”, the new documents do not appear. How can I repair this situation without transfering everything by hand?

I sync via DropBox, and as far as I can tell from viewing the contents of the Sync.dtCloud, the problem does not lie there.

I don’t know when I updated my iMac to DT 11.2. I guess I should have updated the Air as well, but … doh!

The current version of DEVONthink 2.x is 2.11.3. Both machines should be running the most recent version.

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