So with the update to version 11 I noticed that I got a lot of those upper right "meta data needs to be saved" symbols (3 bars with arrow down) on more and more thumbnails (maybe it was a problem before 11 and I didn't notice).
My setup is that I want LR to write xmp files for every image (for backup purpose to be independent from the LRcatalog in an emergency and for sharing photos with others). The setting in Metadata / auto sync active is set.
It syncs fine between LR Mobile/Web and LR Classic.
But it does not seem to update the xmps (if thats what the smybol means, I also noticed missing xmps for fresh raw files that got an edit synced from web).
I can do Metadata / save to file to remove that symbol. But as soon as I change anything in the development module its back.