Make this happen and I am going to do my best to publicize this.
On the other hand, chrome is making it increasingly tough to use any other browser by sheer intuitive and useful features. Grouping tabs for eg. I know other would do it one day. But there is a lag. I wonder why other browsers (OSS) do not straight up copy any good features and release. Assuming there is good enough dev resources.
Or is it really that hard to do it?
Other browsers don't so what you say or are slow to do so for the same reason that the EFF will likely never publicize such an ad campaign against ad-blocking. Not-for-profit organizations of all kinds optimize for either wasting revenue or wasting effort. Just look at where all these organizations are, like Mozilla/Wikimedia/EFF, compared to where they were 15 years ago. They consume more and more money while doing proportionally less with that money. What would have been obvious decisions back then that could be implemented in short order now require bureaucracy that ultimately sidelines what's important for what will inflate the egos of suits. (The same happens to for-profit companies, but that's usually more a function of time and scale rather than time and incentive.)
I suppose there are browsers like Brave that would be in the position to implement Chrome features, which I guess happens by default. But let's just say in the situation where Chrome implements something that doesn't show up downstream in Chromium; Brave's interests might not be in competing directly with Chrome but focusing efforts on BAT/crypto and replacing ads.
Grouping tabs is already possible in Vivaldi. There are also FF extensions, who offer alternative concepts. I think TabTree or something like that it is called.
Firefox has the Simple Tab Groups extension, which works with containers. Chrome not only doesn't have containers, but its tab grouping is clunky and featureless in comparison.
