Obtenha o arquivo do tipo de campo js e loop
// For multiple
$("#my-form").find("input[type=file]").each(function(index, field){
for(var i=0;i<field.files.length;i++) {
const file = field.files[i];
if(file.size > 5242880 || file.fileSize > 5242880) {
errorMessage = 'Files must be less than 5MB.';
alert(errorMessage);
}
}
});
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