Is there a way to change ratings (those little yellow stars) for all books by a single author, or all books in a collection?
Yes. Filter your library by that criterion (e.g. author:Piper, or copy the rule from your Collections tab and paste it into your Library Find box) and then select all the items which match that criterion that you want to rate. Click on the first one and hold the Shift key down as you click on the last one, and a whole contiguous range of titles will get selected. Or Ctrl+Click to selectively select non-contiguous ones. Then you can tag or star them all at once in the Info panel on the right. One caveat: be careful not to click on the cover icon or title column when you select the items in the Library, as that will open the resource. Just click on any of the other columns (Type, Author, etc.)
Outstanding. Thank you!
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