[BUG][A11y] Windows desktop: slash command suggestions render off screen and arrow keys do not move through them

I'm blind. Keyboard and NVDA, no mouse, Claude Desktop on Windows. Second of two reports about popups landing at the bottom of the page instead of next to whatever opened them. The other one is #82288.

Type a slash in the prompt box and a couple of letters of a command name. The list of suggestions opens at the very bottom of the page, below everything else, off screen. So reading my own options means leaving the input and going down the document to find them.

I could work around that. What I cannot work around is that the arrow keys do not touch the list. Up and down move the caret through the letters I just typed. Focus is in the input, which is the only place focus can be while I am typing a command, and from there nothing I have tried changes the selection.

So a slash command only works for me if I already know its exact name and can type the whole thing out from memory. The suggestion list is there so you can find the commands you do not know yet, and that is the half I cannot reach.

What I would expect is a combobox. Focus stays in the input, up and down move the active option, NVDA reads each one as it becomes active, Enter takes it, Escape closes the list, and the list is drawn next to the input rather than appended to the end of the page.

Guessing again, same as the other report: a portalled listbox that was never wired back to the input with aria-controls and aria-activedescendant, and no key handling for up and down while it is open.

Claude Desktop 1.24012.9 from the Microsoft Store. Windows 11 IoT Enterprise LTSC 2024, build 26100. NVDA 2026.1.1.