The image should be a square so that the style can turn it into a completely round circle. (example)
<img class='img-circle' src='..' />
For the img-circle element, the following bootstrap style is applied:
.img-circle { border-radius: 50%; }
Therefore, if the image is rectangular, you will create an elliptical shape. If you want to get around this, you will have to apply a mask to the image. In addition, you could possibly also copy it.
You might be interested in the following question: How does this CSS create a circle? .
Josh crozier
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