I created a module called 'Vendor/CustomsGallery/' that has an image field in it. On Magento 2.3.3 when I try to add a record from the admin area, I get an error 'A technical problem with the server created an error.' when I try to upload an image. I looked at closely at all the code, and compared it to another module I made called 'Vendor/Artists/' that works fine. It appears the issue was the naming of the module. I had to rename it to 'Vendor/Customsgallery' to get it to work.
I created a module called 'Vendor/CustomsGallery/' that has an image field in it. On Magento 2.3.3 when I try to add a record from the admin area, I get an error 'A technical problem with the server created an error.' when I try to upload an image. I looked at closely at all the code, and compared it to another module I made called 'Vendor/Artists/' that works fine. It appears the issue was the naming of the module. I had to rename it to 'Vendor/Customsgallery' to get it to work.