BUG #19711: SSH tunnel with PPK identity file fails/crashes in newer pgAdmin version but works in older version

The following bug has been logged on the website:

Bug reference: 19711
Logged by: Ayoub Cherfaoui
Email address: ayoubcherfaoui19(dot)25(at)gmail(dot)com
PostgreSQL version: 19beta3
Operating system: Windows
Description:

I am experiencing an issue when connecting to a remote PostgreSQL server
through an SSH tunnel using a PuTTY .ppk private key. With the newer pgAdmin
version, the SSH connection fails and I encountered the error Exception:
access violation writing 0x0000000000000000. I also received an SSH
authentication message indicating that no password or public key was
available when using the identity file.

I verified that the SSH server is reachable and that the private key is
valid. After switching back to an older version, the same server
configuration and private key work correctly. This suggests the problem may
be related to SSH/PPK private-key handling in the newer version.

Environment: Windows 11, pgAdmin 4, SSH tunnel using a .ppk identity file,
public-key authentication. The issue is reproducible with the newer version
but not with the older version.