Can't connect to ldaps behind haproxy in M17

I have noticed, that I can not connect to ldaps server which is behind SSL terminated haproxy.

The error seems to be timeout

Error while opening connectionError while opening connection -  ERR_04169_RESPONSE_QUEUE_EMPTIED The response queue has been emptied, no response was found.org.apache.directory.studio.connection.core.io.StudioLdapException:  ERR_04169_RESPONSE_QUEUE_EMPTIED The response queue has been emptied, no response was found. at org.apache.directory.studio.connection.core.io.api.DirectoryApiConnectionWrapper.toStudioLdapException(DirectoryApiConnectionWrapper.java:1350) at org.apache.directory.studio.connection.core.io.api.DirectoryApiConnectionWrapper.access$2(DirectoryApiConnectionWrapper.java:1342) at org.apache.directory.studio.connection.core.io.api.DirectoryApiConnectionWrapper$2.run(DirectoryApiConnectionWrapper.java:483) at org.apache.directory.studio.connection.core.io.api.DirectoryApiConnectionWrapper.runAndMonitor(DirectoryApiConnectionWrapper.java:1261) at org.apache.directory.studio.connection.core.io.api.DirectoryApiConnectionWrapper.doBind(DirectoryApiConnectionWrapper.java:488) at org.apache.directory.studio.connection.core.io.api.DirectoryApiConnectionWrapper.bind(DirectoryApiConnectionWrapper.java:323) at org.apache.directory.studio.connection.core.jobs.OpenConnectionsRunnable.run(OpenConnectionsRunnable.java:114) at org.apache.directory.studio.connection.core.jobs.StudioConnectionJob.run(StudioConnectionJob.java:109) at org.eclipse.core.internal.jobs.Worker.run(Worker.java:63)Caused by: org.apache.directory.api.ldap.model.exception.LdapException: ERR_04169_RESPONSE_QUEUE_EMPTIED The response queue has been emptied, no response was found. at org.apache.directory.ldap.client.api.LdapNetworkConnection.bind(LdapNetworkConnection.java:1578) at org.apache.directory.studio.connection.core.io.api.DirectoryApiConnectionWrapper.bindSimple(DirectoryApiConnectionWrapper.java:339) at org.apache.directory.studio.connection.core.io.api.DirectoryApiConnectionWrapper.access$5(DirectoryApiConnectionWrapper.java:333) at org.apache.directory.studio.connection.core.io.api.DirectoryApiConnectionWrapper$2.run(DirectoryApiConnectionWrapper.java:395) ... 6 moreCaused by: org.apache.directory.api.ldap.model.exception.LdapException: ERR_04170_TIMEOUT_OCCURED TimeOut occurred at org.apache.directory.ldap.client.api.LdapNetworkConnection.bind(LdapNetworkConnection.java:1549) ... 9 more
 ERR_04169_RESPONSE_QUEUE_EMPTIED The response queue has been emptied, no response was found.

In the haproxy log, I can see the connection was made. The ldap servers in the backed are definitely responding properly (I can connect to them directly, and numerous applications are using this haproxy as ldap source, and it works perfectly fine).

I suspect it is something in M17.

When I downgraded to 2.0.0.v20210213-M16, it works fine - I can connect as expected. I have tried M17 with java-16-jdk and java-11-openjdk, no change.

Is there anything I could investigate more and help discovering what the issue might be?