I recently discovered this through GWSL; It is nice that this X server almost supports the keypad correctly. Most X servers only send the keypad as number keys ever, but at least this will send the arrow function keys when numlock is off.
However, the shift key changes the key shift mode, which means using keys like shift-numpad6 (right arrow) doesn't mark anymore, but rather sends '6's when numlock is off, shift still ends up applying.
This hasn't been the behavior of the keypad since DOS days, usually the shift key only changes the keys affected by alpha-lock not num-lock, and numlock only changes the mode of the keypad between numbers and arrow/navigation function keys.
Please make keypad mode only respect numlock, and don't change mode according to shift key.
Practical example: VS Code (An electron app)
In linux, navtive X(or Wayland), num-lock off, numpad keys move normally as arrows, and shift-arrows mark text as expected (even in a field like this message, actually)
In Windows, native behavior, num-lock off, same as above.
In WIndows, using this X Server, shift changes the mode of the numpad keys and sends numbers instead of the arrow key and shift, which would allow marking text for example. I think also shift and numlock - on also changes the mode to send arrow keys, and it shouldn't; that is shift should not affect keys which are affected by numlock but only those keys that are affected by capslock; although it should of course be sent as a control modifier key.
I expect that for a VERY long time that people generally have stopped using the number pad for navigation (having to constantly turn off num-lock when using other people's systems, although in a small percentage of cases where they were being used as POS (point of sale) terminals, having numlock ON made sense, and I would have to remember to leave it on, or the cashiers would not be able to enter numbers, or fix that the keyboard isn't behaving 'normally' on their own. So I do expect there isn't a lot of people paying attention to these little details, but I deliberately get development laptops with a keypad because I appreciate having the arrows and pgup/down home/end all in the same location instead of scattered all over.
If advised where this sort of change might be made I might be able to help make such a modification and submit a pull request (oh, I guess this isn't Github... that makes submitting changes a little harder)
Anyone? Native keypad support? I'm not asking for X to do anything different than behave the same as either the windows system hosting it or the native X for the linux I'm connecting to... I understand interpreting windows keycodes is trickier than most keys, but it's surely still able to be done... you at least send keypad arrow keys with numlock off unlike most.