Problems with upload files pluploader

Pydio 8
24

This is my conf-file: /etc/apache2/sites-available/000-default-le-ssl.conf

  <IfModule mod_ssl.c>
  <VirtualHost *:443>
          ServerAdmin webmaster@localhost
          DocumentRoot /var/www/html
          ErrorLog ${APACHE_LOG_DIR}/error.log
          CustomLog ${APACHE_LOG_DIR}/access.log combined
          SSLCertificateFile /etc/letsencrypt/live/mywebsite/fullchain.pem
          SSLCertificateKeyFile /etc/letsencrypt/live/mywebsite/privkey.pem
          Include /etc/letsencrypt/options-ssl-apache.conf
          ServerName mywebsite.fullyqualified.name
          <Directory /var/www/html>
                  AllowOverride All
                  Require all granted
          </Directory>
          AllowEncodedSlashes NoDecode
          SSLProxyEngine On
          SSLProxyVerify None
          SSLProxyCheckPeerCN Off
          SSLProxyCheckPeerName Off
          ProxyPreserveHost On
          ProxyPass /loleaflet https://127.0.0.1:9980/loleaflet retry=0
          ProxyPassReverse /loleaflet https://127.0.0.1:9980/loleaflet
          ProxyPass /hosting/discovery https://127.0.0.1:9980/hosting/discovery retry=0
          ProxyPassReverse /hosting/discovery https://127.0.0.1:9980/hosting/discovery
          ProxyPassMatch "/lool/(.*)/ws$" wss://127.0.0.1:9980/lool/$1/ws nocanon
          ProxyPass /lool/adminws wss://127.0.0.1:9980/lool/adminws
          ProxyPass /lool https://127.0.0.1:9980/lool
          ProxyPassReverse /lool https://127.0.0.1:9980/lool
 </VirtualHost>
 </IfModule>

pydio installation is directly in in /var/www/html/
the .htaccess file in /var/www/html/ is the following

<IfModule mod_rewrite.c>
RewriteEngine on
RewriteBase /
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule (.*) index.php [L]
</IfModule>

My apache is configured as mpm-prefork.
In the site configuration is also included the part related to collabora.
The real host name has been changed as mywebsite.fullyqualified.name