We've recently been having a problem with a few of our products. We sell highly customizable bicycles, for which the clients are able to choose the color of every single element. This means that there is a ridiculous amount of variations for each of these products. Every time a customer finishes their customization and goes to cart, PrestaShop generates a set of thumbnails and images for the customized bike.
Now, the problem is: these images have become so numerous that we're starting to have trouble with our back-office. When clicking on the product form the catalog, the first page takes upwards of a minute to load, if it ever actually loads; the case when this doesn't happen is shown in the first attached screenshot (sometimes with the white loading spinner, sometimes without). Even when the first page does load, every other tab refuses to load at all, showing a dialog saying "Some of the tabs have not loaded correctly, do you want to reload them?", as shown in the second screenshot. Clicking OK just causes the exact same dialog to appear again a few seconds later, and clicking cancel just gets rid of the dialog. Regardless of what option is chosen on the dialog, clicking on any of the tabs on the left other than the Information tab results in the window being blank, as in the third screenshot.
This is obviously a problem, since we need to change the prices of several of the products and do some maintenance and reconfiguration. Preferences > Images > Move images to new storage system has not yielded any results whatsoever. The excess of images is our best bet for what is happening, since this problem started occurring first on our most popular customizable model (and thus, the one with the most images created for it), before slowly spreading to the rest of the customizable products. We are currently at a loss for which direction to explore, so we'd appreciate some help.
We are running PrestaShop 1.5.2.0. We have tried to upgrade to a newer version of PS to see if that would help with the issue, but so far, due to a combination of error after error after error, it has proven impossible. A thread has been opened in the appropriate subforum for it: https://www.prestashop.com/forums/topic/561393-cant-seem-to-upgrade-to-1520-to-16x/