[is Crop to selection possible]

I too want this feature. It's such a simple workflow I am accustomed with:

1. You select something in the image;
2. You go to Image > Crop selection.
   (Like that. a two-step process. It shouldn't be necessary to create another file in another tab, nor manually align cropping edges)
3. You export, save, whatever suits your needs;
4. You close the file.

Alternatively:

1. You select something in the image;
2. You switch to the crop tool, to notice your selection is already marked as the cropping area;
3. You confirm the action (either enter or double click);
4. You export, save, whatever suits your needs;
5. You close the file.

Photoshop has it, Photopea has it, they say even GIMP has it… It's not any game changing advanced process that shifts paradigms and may restructure the whole UI. It's simply the option to crop the canvas to what has been selected.