Successor indicates that it’s designed to replace it. That’s not the case and never was. They have different purposes. (For the rest, my recollection was defin

Successor indicates that it’s designed to replace it. That’s not the case and never was. They have different purposes. (For the rest, my recollection was definitely off on the timing, and most significantly I forgot the proto-flexbox stuff that Gecko and WebKit had long before grid was proposed. Beyond that, grid certainly took longer to mature, as I remarked, being more complex and needing to interact with more features to be optimally useful. Incidentally, IE got both flexbox and grid (earlier drafts) at the same time, in IE10, Microsoft leading the way on grid by several years, five by the most common way of reckoning.)