I'm just wondering because I want to fix some small bugs and made add some small stuff but if its not allowed I will just wait until the game jam is over
If I'm not mistaken, someone asked Mikkel about it and he replied that it wasn't too late. And I know for sure some people patched their games.
In my case, I patched just the desktop version to fix 2 bugs. ( the ones you found, actually :D ) While the Web version is unchanged. And most just play the Web version as I can see in the analytics.
So if you are unsure, maybe go with an alternative version. You can mention it in the comments so people know that it's not what you submitted in time. :)
But maybe Mikkel will answer here later as well. :)