If remote Docker server cannot be reached, it is not possible to open Plesk > Docker and configure Docker settings. The following error is shown:
"The Docker service is unavailable: Connection timed out".
- Also, it increases a time to open domain settings.
This is Plesk bug with ID #EXTDOCKER-37 which is planned to be fixed in future Plesk updates.
As a workaround, disable problem remote Docker server under Tools and Settings > Docker.