When I try to upload a new icon, it fails with this error. Same with uploading logo image. How do I debug this further?
A technical problem with the server created an error. Try again to continue what you were doing. If the problem persists, try again later.
[update] This is bug in magento 2.3 please check this question answer I’m sure it will help you Magento 2.3.0 "A technical problem with the server created an error." When uploading the logo image