Comparing photos in two, or more, Lightroom folders

I knew I had a mix of duplicate photos, spread over several folders in LR Classic, which I wanted to compare and rationalize. Here's how I did it:

• Go to folder A, select all (Ctrl + a) then set the label colour, e.g. red. Repeat for folder B, but choose a different colour.
• Hold down Ctrl and select both folders.
• Choose Grid View.
• All the photos from both folders are displayed. Photos with same names, but different colour will be adjacent to each other.
• Also, if you go to 'view -> options, you can set the bottom label to 'Folder', so you will see the folder name as well as the colour.
• More than two folders can be compared in this way, just repeat, adding C, D......

Now the photos can be selected individually or as a group and deleted, renamed or dragged to a different folder.

A useful freeware utility for finding duplicate files, in general, is SearchMyFiles, which compares file size as well as name. It's better than the duplicate finder in CCleaner and can also find which files are NOT duplicated.

It might be obvious to some experienced LR users, but I hope some find it useful.