luci: Error "No related RPC reply" in the Network -> Interface section after "attended sysupgrade" to 25.12.0

Is there an existing issue for this?

• I have searched among all existing issues (including closed issues)

screenshots or captures

Actual behaviour

I did the following steps:

1. Sysupgrade to a new version with the GUI, from the menu System -> Attended Sysupgrade from 25.12.0-rc5 to the suggested version 25.12.0
2. Sysupgrade did run without any visible error.
3. After the upgrade, Luci is not showing the correct infos in the Menu Network -> Interface
4. I see the same Luci problem from different machines and from different browsers chrome, Firefox.
5. Only the Luci GUI interface seem to be not working correctly I do not see any "other" problems in the behaviour of the new OpenWrt Version 25.12.0

Expected behaviour

After the sysupgrade the Luci GUI should display correct output.

Steps to reproduce

I cannot confirm that this reoccurs after an new sysupgrade.

Additional Information

# owut check --verbose
owut - OpenWrt Upgrade Tool 2026.01.13~2526d84b-r1 (/usr/bin/owut)
ASU-Server     https://sysupgrade.openwrt.org
Upstream       https://downloads.openwrt.org
Target         ramips/mt7621
Profile        netgear_r6220
Package-arch   mipsel_24kc
Root-FS-type   squashfs
Sys-type       sysupgrade
Version-from   25.12.0 r32713-f919e7899d (kernel 6.12.71)
Version-to     25.12.0 r32713-f919e7899d (kernel 6.12.71)
Build-commit   https://git.openwrt.org/?p=openwrt/openwrt.git;a=shortlog;h=f919e7899d
Build-FS-type  squashfs
Build-at       2026-03-03T00:14:15Z (~4 days ago)
Image-prefix   openwrt-25.12.0-ramips-mt7621-netgear_r6220
Image-URL      https://downloads.openwrt.org/releases/25.12.0/targets/ramips/mt7621
Image-file     openwrt-25.12.0-ramips-mt7621-netgear_r6220-squashfs-sysupgrade.bin
Installed      159 packages
Top-level      133 packages
Default         33 packages
User-installed 101 packages (top-level only)

Package version changes:
All packages are up-to-date

Default package analysis:
  Default                        Provided-by
  nftables                       nftables-json

There are currently package build failures for 25.12.0 mipsel_24kc:
  Feed: packages
    dockerd                      Fri Mar  6 13:23:42 2026 - not installed
    domoticz                     Fri Mar  6 14:41:58 2026 - not installed
    pigeonhole                   Fri Mar  6 13:59:58 2026 - not installed
    pillow                       Fri Mar  6 14:00:01 2026 - not installed
    python-constantly            Fri Mar  6 14:08:38 2026 - not installed
    python-cryptography          Fri Mar  6 14:36:26 2026 - not installed
    python-flask-httpauth        Fri Mar  6 14:50:20 2026 - not installed
    python-frozenlist            Fri Mar  6 14:04:54 2026 - not installed
    python-gevent                Fri Mar  6 14:37:21 2026 - not installed
    python-gmpy2                 Fri Mar  6 14:09:20 2026 - not installed
    python-greenlet              Fri Mar  6 13:58:06 2026 - not installed
    python-multidict             Fri Mar  6 14:05:17 2026 - not installed
    python-psycopg2              Fri Mar  6 14:10:00 2026 - not installed
    python-pyodbc                Fri Mar  6 14:23:12 2026 - not installed
    python-pyopenssl             Fri Mar  6 14:37:42 2026 - not installed
    python-twisted               Fri Mar  6 14:58:12 2026 - not installed
    python-ubus                  Fri Mar  6 14:12:13 2026 - not installed
    python-yarl                  Fri Mar  6 14:22:47 2026 - not installed
    qemu                         Fri Mar  6 13:15:40 2026 - not installed
    rtklib                       Fri Mar  6 11:13:32 2026 - not installed
  Feed: telephony
    asterisk-chan-sccp           Fri Mar  6 15:23:45 2026 - not installed
  Feed: video
    assimp                       Fri Mar  6 12:06:42 2026 - not installed
    glslang                      Fri Mar  6 11:17:29 2026 - not installed
    qt5base                      Fri Mar  6 14:40:26 2026 - not installed
    qt5quick                     Fri Mar  6 14:39:45 2026 - not installed
    qt5quick-controls            Fri Mar  6 14:59:22 2026 - not installed
    qt5script                    Fri Mar  6 14:40:25 2026 - not installed
    qt5svg                       Fri Mar  6 14:40:28 2026 - not installed
    qt5translations              Fri Mar  6 15:31:30 2026 - not installed
    qt5virtualkeyboard           Fri Mar  6 15:31:30 2026 - not installed
    vkmark                       Fri Mar  6 14:24:40 2026 - not installed
31 package build failures don't affect this device, details at
  https://downloads.openwrt.org/releases/faillogs-25.12/mipsel_24kc/

There are no changes, upgrade not necessary
root@tomatoeg:~#

What browsers do you see the problem on?

Chrome, Firefox

Relevant log output

Start by reproducing the reported upgrade path from 25.12.0-rc5 to 25.12.0, then inspect the LuCI Network → Interface page in Chrome and Firefox. Use the reported “No related RPC reply” symptom and the available browser or device diagnostics to identify the affected LuCI entry point; done means the page displays correct interface information after the upgrade.