[Koha] How to hide the OPAC "Cover Not Available" message?

[Victor Barroso Oliveira]

Good night,
How to hide the OPAC "Cover Not Available" message?
I enabled "OPACAmazonCoverImages" and "OPACLocalCoverImages" to insert
images that are not on Amazon.
When he loads the image from Amazon, the message "Cover Not Available" also
appears.
I would like to remove this message when he retrieves the image from Amazon.
Thanks,
Victor