Hi !
First of all sorry for the unclear title, I didn't know how to explain that in a few words so I'll do it below :

It could be nice if Quester had a feature allowing players to redo a quest without earning the related reward !
By eg. : I could define a quest as redoable (no "quest not" condition flag then) but prevent events #10 #11 (rewards and quest points by eg.) to run for players who have already completed this quest one.

Please tell me if something is not clear,
Xibalba7

I can't say I understood much of a word on that one.
Other than you want to allow players to repeat a quest, without getting the reward a second time?

QUEST: Fishing (repeatable)
ACCEPTABLE: NO Requirements
REWARD: $100 (Only The First Time)

And then a second time they get no reward at all?
So basically asking for a quest to become a dud after the first completion? Why would you even want to do that?

Because quests on my server are more elaborated than "go pick 10 blocks and kills 2 cows".

They are either all connected by one big story with roleplay interactions or either tied to the environnement.

By eg. one of those quests is used in a dungeon to add more interaction than simple signs. This quest/dungeon offers jumping puzzles, enigma, etc. to the player.

So no, it wouldn't be a dud. Players asked me to be able to redo some quests so they can accompany a friend or just enjoy the quest a second time.

Reward the questers several times would not be an option because we talk here about big rewards for resolving puzzles for the first time, not for remembering how they manage to do it.

I am not sure personally how this would even be defined in a quest setup. o.o
Though wouldn't it be just as easy to lower the rewards to not only encourage players to repeat quests, but also enable them to do so without receiving large rewards each time?

The way I see it, you're essentially requesting that the plugin determine whether or not this player did this quest already and then if that quest was in fact able to be done a second time but not to grant an "event" because that is what rewards are fired from after an objective is completed.

An alternative to
type: QUESTNOT
quest: 'randomquestnamehere'

Would be?
type: RESTRICT (or something to this effect)
quest: 'randomquestnamehere'
no event: '3,4,5' (being the number event you have listed in your events list) (but events 1, 2 would still go off)

This way it would still allow certain events or things that happened during the quest, but could still blocked the needed "rewards" that were listed in your events list?

Now that I think about it, I do have quests I nerfed myself to make them repeatable but wasn't a huge fan of the thought of giving out an epic item each time it was completed. I had to make that item less epic/last half as long to justify making it a repeatable.

Can I vote this "condition" addition up? xD

This is a bit inconvenient, but possible. You would need to have two versions of one quest, where the first one would not be redoable, and the second one would be redoable and only doable after the first one was done.

I was thinking about being able to add conditions not only to the quest itself, but also assign them to objectives or events. However, this would add even more ballast to the quest and the displayed info, so the main problem to tackle is actually how to implement it well enough.

This is on my to-do list, but is not of very high priority, since it is already possible.