13.3 why is it reuploading all my synced photos?

[Wurstkrapfen]

This is going to take a while uploading everything from scratch and then babysitting multiple Android devices to download again.

Why is this necessary? Did you increase the Smartpreview resolution?

[Rikk Flohr: Photography · Accepted solution]

Lightroom Classic has replaced its sync engine and a complete resync is required to bring your cloud-assets in line with the new schema. 

There is no change to Smart Preview pixel dimensions. 

[Wurstkrapfen]

Wanted to let it rebuild over night, seems it just crahsed at some point (LRC was not running when I came back this morning).

The screen where I could see on what files it's working on is completely gone, right?

[suhas_mutmurdu]

@Wurstkrapfen Sorry to know about the crash. Couple of information needed. 
Did it resume sync once LrC re-started ?
Can you please generate diagnostic report and share it with us ? 
Preference > Lightroom Sync > Press and hold alt/option > Generate diagnostic report

"The screen where I could see on what files it's working on is completely gone, right?"
Yes, "Sync activity" section in Lightroom Preference has been removed. Instead you can use "View sync status on Web " 

Thanks

[Wurstkrapfen]

The web version does not know anything about LRC re-uploading everything, it just says "0 sync errors". So no, it was removed, there is no "instead you can do..". 

Yes it resumed, then I closed it, turned the device off and left for work, I could send a report if it happens again. 

[Wurstkrapfen]

Seems the resync puts all my photos in the "my edits" folder with the time of the re-sync.