Use
code {
font-family: Consolas,"courier new";
color: crimson;
background-color: rgba(0, 0, 0, 0.2);
padding: 2px;
font-size: 105%;
}
armbian-config to freeze firmware. This will set the packages in question to hold.
You can. But if you should is up to you. Mainline support is maturing pretty nicely and I expect to have a decent set of working features in 6.11 which may (or may not) become next LTS kernel. 6.10 is a pretty good preview.
If you are fine with having something older but most hw features working use rockchip bsp, 6.1.43 to say.
This should work with armbian-config as well. Go to Hardware and then Other.