I have updated my store from 4.9.2 to 4.18.1 and all of my thumbnails are half size. Looking through the notes, it seems in 4.10.1 there was a link in an email to restore the original size (dispatch=hidpi.restore) but I only noticed once I got to 4.18.1
I have tried clicking on the link but it just says 404 error - is there any way to manually start this fix?
This dispatch was removed in version 4.12.1 because it was affecting the performance of the admin panel.
To restore this functionality, you can restore the files that were removed at that time. Once you have restored the images, you can delete these files.
You can download the files via this link:
Here are the paths where they have to be placed: app/addons/hidpi/controllers/backend/helpdesk_connector.pre.php app/addons/hidpi/controllers/backend/hidpi.php design/backend/templates/addons/hidpi/views/hidpi/restore.tpl