bug: v3 with icons disabled doesn't show text for <tab> and <space>

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Neovim version (nvim -v)

0.10.0

Operating system/version

Ubuntu 24.04

Describe the bug

Before v3, <tab> and <space> would show for each group.

On v3, with icons disabled (see config below), all groups show the correct letter except from space and tab.

Screenshot from 2024-07-14 08-11-32

This is an old config showing <space> and <tab> in case it helps

Screenshot from 2024-07-14 08-12-06

Steps To Reproduce

Plugin config:

  {
    'folke/which-key.nvim',
    event = 'VeryLazy',
    opts = {
      icons = {
        rules = false,
      },
      spec = {
        {
          mode = { 'n', 'v' },
          { '<leader><tab>', group = 'tab' },
          { '<leader>b', group = '[b]uffer' },
          { '<leader>c', group = '[c]ode' },
          { '<leader>e', group = 'Tree [e]xplorer' },
          { '<leader>f', group = '[f]ile' },
          { '<leader>g', group = '[g]it' },
          { '<leader>gh', group = '[h]unk' },
          { '<leader>s', group = '[s]earch' },
          { '<leader>u', group = '[u]i' },
          { '<leader>w', group = '[w]indow' },
        },
      },
    },
  },

Expected Behavior

<space> and <tab> should show when icons are disabled.

Health

which-key: require("which-key.health").check()

- OK Most of these checks are for informational purposes only.
  WARNINGS should be treated as a warning, and don't necessarily indicate a problem with your config.
  Please |DON't| report these warnings as an issue.
- WARNING |mini.icons| is not installed
- OK |nvim-web-devicons| is installed

Checking for issues with your mappings ~
- OK No issues reported

checking for overlapping keymaps ~
- WARNING In mode `n`, <gc> overlaps with <gcc>:
  - <gc>: Toggle comment
  - <gcc>: Toggle comment line
- WARNING In mode `n`, <yS> overlaps with <ySS>, <ySs>:

- WARNING In mode `n`, <ys> overlaps with <yss>:

- OK Overlapping keymaps are only reported for informational purposes.
  This doesn't necessarily mean there is a problem with your config.

Checking for duplicate mappings ~
- OK No duplicate mappings found

Log

No response

Repro