I am running a 1.27 MW and was installing this extension. As I understand it, the extension distributor packs up and sends out a specific commit from the extension's git repo, in this case it looks to me like commit with id ca0248090a5cc557d27516415dc3324635b0dd99 . When I git clone the extension from github, I can see that this commit is indeed the tip of the REL1_27 branch, which is as expected.
But, the contents of the code delivered via the extension distributor does not appear to be equivalent to the contents of the code you see when checking out REL1_27 from the git repo. The extension distributor for example has the newer extension.json scheme.
Am I misunderstanding something here? I'd prefer (for the time being) to git clone my extensions, but I'm not entirely sure now which commit is the one which is expected to work with MW 1.27.3.
Thanks!