In sync if you long press on a comment it'll collapse all children... admittedly it's different than what you were describing but it'll have a similar effect. Lmk if you want a screenshot or something.
And you can toggle it to be single click, not hold because sync likes config options
Same in Connect ;)
You can also hide the clicked (parent) comment too. I don't personally use it, to keep an overview, but it allows going through comments with much less scrolling.
In sync if you long press on a comment it'll collapse all children... admittedly it's different than what you were describing but it'll have a similar effect. Lmk if you want a screenshot or something.
And you can toggle it to be single click, not hold because sync likes config options
Same in Connect ;)
You can also hide the clicked (parent) comment too. I don't personally use it, to keep an overview, but it allows going through comments with much less scrolling.