This is absolutely frustrating, but I am not sure if the following is an issue only on my machine or with IDLE in general.
When attempting to print a long list in th
The Squeezer extension addresses this problem. Instead of displaying the long text (which is the source of the slow-down), Squeezer captures the output and displays a button instead. You have the option of expanding the contents or viewing it in Notepad.
Squeezer is included in IdleX, which you may find useful.