gitk bug: Disabling "Themed widgets" breaks preferences dialogue

I use Alpine Linux 3.22 (latest).

Recently gitk's preferences window refuses to open.

This seems to be a direct result of switching off the "Themed widgets" setting, which is my preferred choice.

Error message:

invalid command name "::combobox"
invalid command name "::combobox"
    while executing
"${NS}::combobox $page.wrapcomment -values {none char word} -state 
readonly  -textvariable wrapcomment"
    (procedure "prefspage_general" line 41)
    invoked from within
"prefspage_general $notebook"
    (procedure "doprefs" line 27)
    invoked from within
"doprefs"
    invoked from within
".#bar.#bar#edit invoke active"
    ("uplevel" body line 1)
    invoked from within
"uplevel #0 [list $w invoke active]"
    (procedure "tk::MenuInvoke" line 50)
    invoked from within
"tk::MenuInvoke .#bar.#bar#edit 1"
    (command bound to event)

Steps to reproduce:

  $ rm -f ~/.gitk ~/.config/git/gitk
  $ cd <git-repo>
  $ gitk
  Edit -> Preferences
  Uncheck "Use themed widgets"
  Ok
  File -> Quit
  $ gitk
  [error]
  Ok
  [empty preferences window opens]

$ cat /etc/alpine-release 3.22.1

$ apk info git tk tcl git-2.49.1-r0 description: Distributed version control system

git-2.49.1-r0 webpage: https://www.git-scm.com/

git-2.49.1-r0 installed size: 6568 KiB

tcl-8.6.16-r0 description: The Tcl scripting language

tcl-8.6.16-r0 webpage: https://www.tcl-lang.org/

tcl-8.6.16-r0 installed size: 4244 KiB

tk-8.6.16-r0 description: GUI toolkit for the Tcl scripting language

tk-8.6.16-r0 webpage: https://www.tcl-lang.org/

tk-8.6.16-r0 installed size: 1926 KiB