Dropzone showing the V&X icons below the drop box - dropzone.js

Question

My Flask project with Dropzone implementation dont show the file upload progress bar but rather both the 'V' and 'X' icons for each file, like this (the 'v' and 'x' icons are bearly visible below the file name):
, and they appear below the drop box, together with the file name and size, instead of inside the drop box. The files gets uploaded though, but the behaviour is undesired. Has anybody encountered the same problem?
HTML part:
<form id="myProjFileUploadForm" method="post" enctype="multipart/form-data" action="{{ url_for('projects.projects_file_upload') }}">
...
<div id="myFileDropContainer" class="dropzone dz-clickable" style="visibility: hidden">
<div class="dz-default dz-message">
<button class="dz-button" type="button">
Drop files here to upload.
</button>
</div>
</div>
...
</form>
script part:
Dropzone.autoDiscover = true;
myDropzone = new Dropzone("#myProjFileUploadForm", {
autoQueue: true,
clickable: ".dropzone",
paramName: 'file',
url: '/upload',
myFileDropContainer: "#myFileDropContainer",
chunking: true,
forceChunking: true,
retryChunks: true,
retryChunksLimit: 10,
maxFilesize: 2025, // The max file size in Mbytes that is allowed to be uploaded
chunkSize: 10000000, // The chunk size in bytes
autoProcessQueue: true,
timeout: 180000000,
maxFiles: 500000
});
// The function that is invoced when files are dropped in
myDropzone.on("complete", function (file) {
let sStatus = new String(file.status);
let objThisFile = file
sStatus = sStatus.trim();
let sFileName = new String(file.name);
let sLastModifiedDate = new String(file.lastModifiedDate);
let sSize = new String(file.size);
const myObjFile = {
FileName: sFileName, LastModDate: sLastModifiedDate, Size: sSize
}
if (sStatus == 'success') {
$.ajax({
"url": "{{ url_for('projects.save_file_info_to_database') }}",
"type": 'POST',
"data": JSON.stringify(myObjFile),
"contentType": "application/json",
"dataType": 'json',
success: function (response) {
bErr = response.result;
if (bErr) {
objThisFile.status = 'error'
let sErr = response.msg.toString().trim();
if (sErr.length > 0) {
//alert(sErr);
}
}
else {
myDrawFileTable();
}
}
})
}
else {
let sErr = "The following file failed to upload: " + sFileName;
//alert(sErr);
}
});