Unfortunately, with access to neither the Chrome source code nor the Grammarly source code, we can only guess.
Is this what the "open source" movement has created --- developers who are totally lost without source code and refuse to dig deeper? Of course the corporate interests who don't want us to know the truth, because their profit depends on it, would absolutely adore such propaganda...
I still remember a time when a lot of people would disassemble, understand, and patch programs without source --- and many of them weren't even career developers; it was just a way to get software to do what one wanted, and driven by that motivation, one would naturally learn enough to do so.
The article also touches on another point worth mentioning: the amount of complexity in the whole stack is insane. Seeing all the frameworks upon frameworks being name-dropped, I can't help but feel like a lot of this is self-inflicted.
When I removed loader-spinner.gif, the placeholder we display while the menu options load, the page stopped crashing.
Do menu options take long enough to load that they need a loading animation?