Sorry, a quick search doesn't turn it up. This is from memory. Microsoft's strategy - from their own memos (maybe the Halloween memos?) - was to "try to make using Netscape a jarring experience". They were paying (maybe in equipment or some kind of freebies) websites that included at least three IE-only elements in their pages.
This was not just competition. This was a deliberate campaign to break the web in a way where IE would work but Netscape would not.
As I said, this is from memory, and I can't find the source. I have read a copy of the Microsoft memo, though (but you only have my word for it...)
My memory is different, obviously. The IE team took great pains to implement Netscape additions even when they were not standards so that the IE rendering was as good. I never heard of any attempt to make Netscape look worse. That doesn't mean it never happened, but I followed the story very closely at the time.
Microsoft was much more co-operative than Netscape in the early days. It was one of Microsoft's advantages when Netscape was winning and running on pure arrogance. See How the Web Was Won, High Stakes No Prisoners and a few other books for details.
Microsoft did introduce ActiveX, which Mozilla considered supporting, and then decided not to.
I think Microsoft tried to make everything that worked on Netscape work on IE. This was going the other direction - making stuff that worked on IE but didn't work on Netscape, and trying very very hard to get people to write pages that used those things. By having a strict superset, and getting people to use parts that were in the superset but not in the base set, they could effectively make the web IE-only.
I was following it very closely and didn't see that. It seems to me that if Microsoft was implementing Netscape's additions, Netscape could have implemented Microsoft's.
One of the facts of the case is that Microsoft got as close to the standards bodies as it could, and part of its marketing was that it was making IE more standards compliant than Netscape. This is actually very common in computer history (the market leader does whatever it wants to innovate, while the losers band together around standards).
In the end, of course, it didn't matter. Microsoft out-programmed Netscape and then Netscape made several disastrous decisions that amounted to browsercide.
As I said, if you've got any evidence, I'm interested. Specifically, what did Microsoft add that was non-standard and that Netscape couldn't have added?
As far as I know, not even ActiveX qualifies. I discussed this with Mitchell Baker, and she clearly said that Mozilla could have implemented ActiveX if they had wanted to.
This was not just competition. This was a deliberate campaign to break the web in a way where IE would work but Netscape would not.
As I said, this is from memory, and I can't find the source. I have read a copy of the Microsoft memo, though (but you only have my word for it...)