I've all but given up on Firefox at this point, since they've gone to such great lengths to Chromify their browser that it makes more sense to just use something like Brave at this point. That said, it would be ridiculous if they do this, when there are already multiple addons (as mentioned in the article) that can already achieve it (and probably better and with more options and customization than a built-in solution), yet it's been *years* since the features of TMP, especially multiple rows, have been difficult to impossible to get back. Users have been asking for these features back with no response from Mozilla, and so for them to instead add a feature that's already available would just be further snubbing their users. Mozilla has ruined Firefox and ignored the users that *made it* as popular as it was/is all to appeal to the masses and try to emulate Chrome to draw those users, but most of those users don't know or care about other browsers and won't switch anyway, certainly not just to go to something so similar, and in the process they've removed most of what makes Firefox worth using for those that do care.