Add regression/integration tests for FRONTEND_PATH behaviour #5837
Description
There have historically been issues with FRONTEND_PATH behaviour being broken by subsequent releases.
Implementing regression tests will help to prevent future instances of this. In addition they will help to clarify the intended behaviour of this environment variable.
The PR #5712 proposes a set of integration tests using the playwright framework. This would close the issue and form the basis for future hardening of this feature.