This command is also known as the 'instant construction' cheat, it enables and disables (toggles) quick build. When quick build is enabled, all of your constructions will be completed within one day (regardless of how long they usually take).
The syntax for the quickbuild command is as follows:
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Find below working examples of the quickbuild command.
If quick build is disabled (default), this command will turn quick build on, making constructions take only 1 day to complete. If quick build is enabled, using this command will toggle it off.