bug: scroll mappings not working in nvim 0.10

[willothy]

Did you check docs and existing issues?

• [X] I have read all the which-key.nvim docs
• [X] I have searched the existing issues of which-key.nvim
• [X] I have searched the existing issues of plugins related to this issue

Neovim version (nvim -v)

NVIM v0.10.0-dev-1081+gf859d16ae

Operating system/version

Arch Linux, 6.4.12-arch1-1

Describe the bug

Scroll mappings do not work at all in the popup menu when running nvim 0.10 (master). They do work correctly in 0.9.

Steps To Reproduce

1. Install which-key
2. Create a long list of mappings under one key "namespace"
3. Open the menu, and attempt to scroll to see hidden keys
4. Nothing happens

Expected Behavior

The popup menu should scroll up/down when pressing <c-u> / <c-d>.

Repro

-- DO NOT change the paths and don't remove the colorscheme
local root = vim.fn.fnamemodify("./.repro", ":p")

-- set stdpaths to use .repro
for _, name in ipairs({ "config", "data", "state", "cache" }) do
  vim.env[("XDG_%s_HOME"):format(name:upper())] = root .. "/" .. name
end

-- bootstrap lazy
local lazypath = root .. "/plugins/lazy.nvim"
if not vim.loop.fs_stat(lazypath) then
  vim.fn.system({ "git", "clone", "--filter=blob:none", "https://github.com/folke/lazy.nvim.git", lazypath, })
end
vim.opt.runtimepath:prepend(lazypath)

-- install plugins
local plugins = {
  "folke/tokyonight.nvim",
  { "folke/which-key.nvim", config = true },
  -- add any other plugins here
}
require("lazy").setup(plugins, {
  root = root .. "/plugins",
})

vim.cmd.colorscheme("tokyonight")
-- add anything else here

local wk = require("which-key")

-- big list of g mappings for convenience, since g is a builtin prefix
wk.register({
  g = {
    a = { "", "" },
    b = { "", "" },
    c = { "", "" },
    d = { "", "" },
    e = { "", "" },
    f = { "", "" },
    g = { "", "" },
    h = { "", "" },
    i = { "", "" },
    j = { "", "" },
    k = { "", "" },
    l = { "", "" },
    m = { "", "" },
    n = { "", "" },
    o = { "", "" },
    p = { "", "" },
    q = { "", "" },
    r = { "", "" },
    s = { "", "" },
    t = { "", "" },
    u = { "", "" },
    v = { "", "" },
    w = { "", "" },
    x = { "", "" },
    y = { "", "" },
    z = { "", "" },
    A = { "", "" },
    B = { "", "" },
    C = { "", "" },
    D = { "", "" },
    E = { "", "" },
    F = { "", "" },
    G = { "", "" },
    H = { "", "" },
    I = { "", "" },
    J = { "", "" },
    K = { "", "" },
    L = { "", "" },
    M = { "", "" },
    N = { "", "" },
    O = { "", "" },
    P = { "", "" },
    Q = { "", "" },
    R = { "", "" },
    S = { "", "" },
    T = { "", "" },
    U = { "", "" },
    V = { "", "" },
    W = { "", "" },
    X = { "", "" },
    Y = { "", "" },
    Z = { "", "" },
  },
})

[willothy]

Edit: found the offending upstream commit, merged with https://github.com/neovim/neovim/pull/24824.