I know Microsoft was notorious for not playing nice with other browsers but I thought that mostly had to do with them deciding to go their own way with non-stan

I know Microsoft was notorious for not playing nice with other browsers but I thought that mostly had to do with them deciding to go their own way with non-standard features or simply not implementing standards they don't like Is there documented evidence that Microsoft stooped this low as well? Did they purposely make their sites not work as well on other browsers?