Let's say: you are moving (or copying) folder "A" from Downloads to Documents. The Documents already contain a folder named "A."
In this case, by default, you will not be notified that the destination folder contains a folder with the same name and the folders will get merged.
Unlike the above situation, if you want to get notified and choose about merging folders, then follow the below steps:
That is all. From now on, you'll be shown a confirmation popup if the destination location contains a folder with the same name while copying or moving a folder into it.
Note: Keep in mind that the "Hide folder merge conflicts" option does not affect the confirmation popup that appears if the destination location has a file with the same name while copying or moving a file into it (see below screenshot).
If you want to go back to the default, select "Hide folder merge conflicts" and then hit "OK."
I hope that this guide is useful to you. If you find the information in this post useful, share with your friends.
How to Hide or Show Folder Merge Conflicts in Windows 10