my forum software just tells the user that the posting is too long and suggests to use more-tags (and subtracts already used more-tags from the size of the posting). otherwise it prevents the user from posting.
this is the easier part; automatic insertion of such tags would be more complicated.

In reply to Re: Functionality to automatically insert <readmore> tags into long posts? by tinita
in thread Functionality to automatically insert <readmore> tags into long posts? by OfficeLinebacker

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