This reminds me of similar issues I've encountered as a software engineer. I first ran into this issue about a decade ago, albeit not because of Grammerly,but due to some specific gif causing web app to crash. Both times the gifs were animated. Happened years apart and at different companies.

I see some comments highlighting RAM, which could totally have been the issue. Totally looking forward to a follow up to this later down the road, I am sure this isn't going to be the last time we hear of this.