(Re-)posting this as my last idea has gone AWOL.
Prior to the move to web-extensions, there were (clunky) add-ons that could divide the browser into two or more panes. This was especially useful since most people have widescreens and the modern web (aka mobile-first) wastes space on the sides. Unfortunately, web extensions has crippled these add-ons and we're stuck "tiling" or "cascading" windows like it's 1995!
Please allow us to view 2, 3, 4 or more pages at once, this will allow huge productivity gains.
MS is experimenting with this in Edge:
Vivaldi showing how its done (viewing three tabs at once!):
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Hey @KERR ... I think your previous post is in moderation (perhaps after an edit). Let me approve it and make it public again so you don't lose votes, comments, etc.
Okay, it should be visible here: Split-screen/Tab-in-Tab feature (view more than one tab at once)