New answers tagged slices
If they look similar to this.... They are color samples. They are created by using the Color Sampler Tool and clicking an image. To remove them grab the Color Sampler Tool and Option/Alt click them. (The cursor will change to little scissors when you hover over them with Option/Alt depressed.)
You've accidentally turned on Slices. Slices are a web technology to break up an image into separate areas for exporting. Here's the thing you need to untick to hide it.
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