How to enable profiler in symfony 4

I've just installed new project and I can confirm that the profiler and toolbar are enabled by default. Configuration is found in config/packages/dev/web_profiler.yaml with the following configuration:

web_profiler:
    toolbar: true
    intercept_redirects: false

framework:
    profiler: { only_exceptions: false }

Please be aware, that you have to attach web_profiler routes.

in:

config/routes/dev/web_profiler.yaml

web_profiler_wdt:
resource: '@WebProfilerBundle/Resources/config/routing/wdt.xml'
prefix: /_wdt

web_profiler_profiler:
resource: '@WebProfilerBundle/Resources/config/routing/profiler.xml'
prefix: /_profiler