'That is not a valid source path / URL' when clicking "Check out in Sourcetree" from bitbucket

[Jonathan Adlerstein]

I've seen several other discussions on a similar topic but none of them or their resolutions resolved this issue.

1. I started with an issue in JIRA
2. I clicked "create branch"
3. Followed the form to clone from a master branch.
4. Clicked the "Check out in Sourctree" button.

Sourcetree opens and I'm presented with the main Sourcetree window, an orange Error "This is not a valid source path / URL" and a blue "URL Actions" window.

Steps I have taken to attempt resolution are below. I re-attempted after each step.

1. I have git installed on my machine and have tried switching to embedded git in Sourcetree.
2. I enabled and downloaded embedded Mercurial in Sourcetree.
3. I've successfully configured my SSH key and can view and clone and fetch repos from bitbucket within Sourcetree directly.
4. I switched to an App Password and verified connectivity.
5. I changed my authentication protocol to HTTPS and verified connectivity.
6. I switched my authentication to basic and verified connectivity.

I consistently get the same error message and am unable to check out the branch in Sourcetree.