Yeah, KIO is an awesome piece of software. Yesterday, a fuse interface was released[1] so that non-KDE software in Plasma also get most of the benefits of KIO.
And speaking of browser tabs, Plasma Browser integration allows to switch to an open tabs from Krunner directly and it works with Firefox, Chrome and Microsoft Edge.
[1]: https://feverfew.home.blog/2020/12/31/kio-fuse-5-0-0-release...