Visual bug: decimals are not shown for numbers higher than 1 Sx.
Since this is an idle/incremental game, I'm not sure if this is an "end-game bug", but x200 upgrade multiplier seemes to work corretcly, and 200th Lemonade Stand costs over 1 Sx so I consider this as a regular bug.
Viewing post in Idle Capitalist comments
The numbers are still bugged. After 1*10^24, the game shows 10*10^25 and then 100*10^26. Correctly, it should show either 1*10^25 and 1*10^26 (scientific notation), or 10*10^24 and 100*10^24 (engineering notation). The way the game currently shows number is an incorrect mixture of these two notations.