Hi there, Not sure if you've resolved this already but I just had the same problem and found the solution through Lightroom Classic. Go into Lightroom Classic, select preferences> lightroom sync tab > select 'delete all synced data', it will open chrome then you can delete the lightroom library online, this will not affect the files stored on your hard drive. To be safe, perhaps just move the originals from the folder they are currently in to something with a different name. Will post screenshots of the process below. I guess they want everyone to upgrade their cloud storage accounts to host the files so they are making it super difficult to find the delete option. surely they are aware that the majority of photographers use terabytes of data for their library? I'll be sticking to external hard drives until cloud storage matches the price of physical hard drives! hope this helps.
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