Hi there!
Thank you for contacting us! Sorry to hear that you have problems with the plugin.
We had another user report this issue as well. Unfortunately we were not able to reproduce this issue in any of our environments and we are currently awaiting feedback from the other user to get to the bottom of the issue.
If you want to help us as well, could you please send us a message at support@tinypng.com so we can give you further instructions?
Otherwise we will let you know once we have solved the issue!
I’ve also been experiencing this issue, I will send you folks an email.
I am no longer experiencing the issue.
I have my blog hosted on Pantheon, with a reverse proxy through Fastly.
When trying to access the Bulk Optimization plugin via our own domain name, images would “cancel” and I would get console errors
503 error: /wp-admin/admin-ajax.php
and
Cannot read property 'image_sizes_optimized' of null
But when I access the plugin via the admin panel directly on the Pantheon environment, and not through our domain, it works no problems.