I have an issue where sometimes the editor does not load, url: wp-admin/upload.php?page=pte-edit&pte-id=228
failed Uncaught TypeError: Cannot read property '0' of undefined main.js:814 Uncaught Error: Load timeout for modules: cs!csmain_unnormalized2 http://requirejs.org/docs/errors.html#timeout
Instead I get a JS error and nothing shows up at all.
It feels to me like a race condition due to it sometimes working.
I have been investigating the ajax call 'get-thumbnail-info', I thought maybe that was running before the page is ready for content.