Example using Rails 5.2 and JCrop for user cropping of images. activestorage branch replaces carrierwave with ActiveStorage. Bootstrap is also include on the IntegrateBootstrap branch.
Ruby
Sample Rails App for Browser-Side Image Cropping with JCrop
master branch uses Rails 5.2, JCrop and CarrierWave
activestorage branch uses Rails 5.2, JCrop, and ActiveStorage
IntegrateBootstrap branch includes Rails 5.2, JCrop, and ActiveStorage along with bootstrap for styling