iLounge:

Apple has debuted a major update to its web-based iCloud Photos app at iCloud.com, presenting a new user interface that more closely resembles the macOS Photos app. A new sidebar is enabled by default which provides more streamlined browsing of photo albums, although as in the corresponding macOS app, users can choose to toggle the sidebar off using a button at the top of the screen. Multiple photos can now be selected, and action buttons in the top-right corner will apply to all selected photos, allowing you to share, download, delete, or file several photos at a time; individual photos can also be organized into albums via drag-and-drop into the sidebar. Viewing an individual photo also now displays a carousel of thumbnails at the bottom of the screen, allowing you to quickly browse through other photos in the same album.

I don’t use iCloud Photos but this looks like a decent update to start bringing it more in line with macOS Photos app.