Hi there,
I’m not sure what kind of problem is on Beta versions of Local, but you can try this while they manage to solve this bug.
You can download Adminer from its official website https://www.adminer.org/ now is version 4.7.5, and include it in the root directory of your project, as project I mean your WordPress local web.
Same problem for me …
I am using Local Lightning 5.0.6 (beta) which is great, but each time I run Adminer I get the “no extension” error message.
Will the problem be fixed with the next beta release?
A big thank to the dev Team