!block is a command for Special:Chat that allows any user who can block users to block users entering a simple syntax on the message input.
To use !block, the following data must be entered into the textbox:
!block USER | REASON | EXPIRY
To set options for the block, there are 3 additional options you can add to the command:
!block USER | REASON | EXPIRY | disable talk page | disable autoblock | disable reblock
The last 3 options do not have to be in the order you seen, but they must go after the expiry in order to work.
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