Remember git passphrase in WSL

I run Windows 10 with WSL. I have the desired behaviour on one computer, but cannot replicate elsewhere. Here's what I'm after:

1. First time I run a remote git command using my ssh key, git prompts me for the passphrase
2. Subsequent times no prompt, including in new terminal windows (I use ConEmu)
3. When all console windows are closed, back to #1

Things I've tried:

• using eval $(ssh-agent), followed by ssh-add; it will remember the passphrase, but if I put it in my ~/.bash_profile then it prompts me for every new console window, and I open a lot - many of which I'm not using git in.
• setting git config --global credential.helper to cache or store
• everything here
• using bash.exe and wsl.exe to get git-credentials-manager.exe to work

Here's an example of what I've put in my ~/.gitconfig: [credential] helper = "/mnt/c/Program\\ Files/Git/mingw64/libexec/git-core/git-credential-manager.exe"

I've installed the git credential manager from here and have also tried the main Git For Windows installation as an alternative.

How can I encourage it to remember my passphrase?

I tried the option to add AddKeysToAgent yes to ~/.ssh/config but it doesn't keep it between new tabs on the terminal.

The best solution I found so far is to do the following:

sudo apt install keychain

Find your hostname using the terminal:

hostname

Then add the following to your ~/.bashrc or ~/.zshrc file:

/usr/bin/keychain --nogui ~/.ssh/id_rsa
source $HOME/.keychain/YOUR-HOSTNAME-HERE-sh

Now, each time you reboot, you’ll have to enter your passphrase. But you only have to do it one time until you reboot or terminate WSL.

If you want to use the same key you already have on Windows you can follow this post Sharing SSH keys between Windows and WSL 2