The answer from Henryh worked for me the first time, and again when I forgot and came back to this forum.
Dropbox backups will not allow me to Save for Web from Photoshop sometimes. It works fine for days or weeks, then suddenly it won't.
(I'm on a 2015 iMac with Mojave os; you may not have this issue on a newer system.)
These are the instructions that I received from Dropbox live chat (with my notes in parens) and after I did these, I was able to Save for Web again.
- Open your Dropbox desktop app
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