Had this issue appear recently, not sure what changed. Maybe because I unlocked the "Poke Mart" option on the UI? Either way, at certain window sizes, the game tries to add the scroll bar, then decides to get rid of it, and repeats this infinitely and just keeps jittering back and forth
#Window confusion?
arctic compass
forest marsh
Happens when the modules there barely fit in your screen (height-wise)
In this case it's the quest one hitting the bottom
Maybe consider changing it to 5 columns so you get more space?
arctic compass
Maybe consider changing it to 5 columns so you get more space?
That becomes an issue when you have 9 copies open 
forest marsh
How?
arctic compass
Because I only have so much screen space, so making them all bigger..
forest marsh
Do you really need to stare at every single module for each client?
In any case, that's besides the point. It's known. Not sure if it can even be fixed. I think it's Boostrap? How about changing the theme then? Some are a bit smaller?
turbid anvil
https://developer.mozilla.org/en-US/docs/Web/CSS/scrollbar-gutter you can reserve space for the scrollbar so that the layout always stays stable