Change current jester goal as:
Be lynched on a condition Everyone must vote or Be lynched and Abstainers must lose/die
For short: Jester wins when jester is lynched and all possible abstainers lose.
All abstainers on jester lynched trial must either die or lose the game at the end.
If no abstainer, then jester wins too.
People are asking for a harder jester,
That will do it.
Strategy-Wise:
If a jester get one guilty vote while majoriy abstains, the jester will get in trouble of winning because it is impossible to have everyone lose.
The proper strategy will be getting ride of some inactive voters and get lynched in the half way in the game, make a proper defense and put its bet on that the loser side will abstain
OR
simply make sure everyone will vote.