CI_ENVIRONMENT = development not working

Hello,

I installed the CI 4.4.5 on my server and all is working fine except when I enabled development mode in .env file "CI_ENVIRONMENT = development" it is not working as expected.
Debug bar is appeared that means the development mode is enabled.
When I tried to imitate some php erorr, then page is showing only "Whoops! ...".
I see the error details in a log file (writable/logs).
I know that it should also be appeared in a webpage with detailed error tracing (it worked in previous releases).

What I need to configure to see the error trace details in webpage?

Thanks in advance,
best regards,
Romans