Guacamole v1.3.0 RDP Sessions disconnects after seconds after upgrading from v1.2.0

I have an on premise Guacamole Server which was running version 1.2.0 in Debian 10 buster without any issue. However, after upgrading to version 1.3.0, using guacamole-server source code and guacamole-1.3.0.war downloaded from official website, I cannot connect to any of my servers using RDP. 

Looking at /var/log/syslog, I get the following:

_{Apr 8 14:06:00 guacamole2 guacd[14125]: Creating new client for protocol "rdp"
Apr 8 14:06:00 guacamole2 guacd[14125]: Connection ID is "$05e76f93-eeac-44e6-a597-e2fed351dae9"
Apr 8 14:06:00 guacamole2 guacd[14399]: Security mode: NLA
Apr 8 14:06:00 guacamole2 guacd[14399]: Resize method: reconnect
Apr 8 14:06:00 guacamole2 guacd[14399]: User "@6d106a47-e2a6-4953-ba8c-d94377344afd" joined connection "$05e76f93-eeac-44e6-a597-e2fed351dae9" (1 users now present)
Apr 8 14:06:00 guacamole2 guacd[14399]: Loading keymap "base"
Apr 8 14:06:00 guacamole2 guacd[14399]: Loading keymap "es-es-qwerty"
Apr 8 14:06:01 guacamole2 guacd[14399]: Connected to RDPDR 1.12 as client 0x0791
Apr 8 14:06:01 guacamole2 guacd[14125]: Connection "$05e76f93-eeac-44e6-a597-e2fed351dae9" removed.}

Looking at /var/lib/tomcat9/logs/catalina.out, I get this:

_{[2021-04-08 14:06:00] [info] 14:06:00.074 [http-nio-8080-exec-5] INFO o.a.g.tunnel.TunnelRequestService - User "tlosada" connected to connection "1".
[2021-04-08 14:06:02] [info] 14:06:02.165 [Thread-28] INFO o.a.g.tunnel.TunnelRequestService - User "tlosada" disconnected from connection "1". Duration: 2091 milliseconds}

No exceptions nor errors. This is what I get in my screen:

FreeRDP version is the following: freerdp2-dev is already the newest version (2.0.0~git20190204.1.2693389a+dfsg1-1+deb10u2).