acirnep

The linked page is clear and well written, but it doesn’t tell me anything I didn’t know before.

I understand what Regenerate Thumbnails does, and I did run it because I thought that the many copies I had were clutter created by the several plugins and themes I tested before setting on Customizr.
Instead I discovered that they all come from Customizr.

After a bit more digging I found the following lines in class-fire-init.php

//Default images sizes
          $this -> tc_thumb_size      = array( 'width' => 270 , 'height' => 250, 'crop' => true ); //size name : tc-thumb
          $this -> slider_full_size   = array( 'width' => 9999 , 'height' => 500, 'crop' => true ); //size name : slider-full
          $this -> slider_size        = array( 'width' => 1170 , 'height' => 500, 'crop' => true ); //size name : slider
          $this -> tc_grid_full_size  = array( 'width' => 1170 , 'height' => 350, 'crop' => true ); //size name : tc-grid-full
          $this -> tc_grid_size       = array( 'width' => 570 , 'height' => 350, 'crop' => true ); //size name : tc-grid

(here in the snippets section only three are mentioned)

So the mystery of where these other image sizes come from is solved.

But I still have a problem: apart from the featured image size (270×250) I am never going to use them because most of the time they look terrible with my pictures (mostly studio pictures and vertical potraits. So I end up with stripes of objects and bellies. Not cool.)
How can I prevent them from being created?