When trying to load the ssh agent by uncommenting the line in user-profile.cmd :
The agent load in a sub ms-dos context and I'm not able to use ssh-add to add my keys.
Typing exit makes the sub context to be closed and then I get my keys loaded.
Below is the difference between previous and current default configuration

If I use the previous configuration, everything works as expected
Same kind of behavior is also when using start-ssh-agent.cmd

Adding that -new_console parameter does not help.
I have the same, bad behaviour.
Have a look at #1807 and #1781
call "%GIT_INSTALL_ROOT%/cmd/start-ssh-agent.cmd" /k exit is what current versions of cmder has in user_profile.cmd
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Have a look at #1807 and #1781