Tuxedo Computers for sure. KDE also wants to partner with Framework, and Slimbook already makes KDE laptops.
Lenovo, Dell and HP are terrible IMO. Not only are the not Linux focused but also terrible companies. The Linux laptops they make are just to target developers meaning: fix your own software issues π Dell for example has had webcam issues on Linux for ages with their MIPS or whatever cameras and simply don't give two shits.
Support a real Linux laptop vendor like the one mentioned above. Not only do they contribute to Linux and open source in general, but I find they are more accessible in terms of support, and they do pretty well in terms of making Linux work on their hardware.