Opening devtools with globally disabled local storage shows white screen

[gordon-quad]

Version info:

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qutebrowser v3.6.2
Git commit: 
Backend: QtWebEngine 6.10.1
  based on Chromium 134.0.6998.208
  with security patches up to 142.0.7444.162 (plus any distribution patches)
  (source: api)
Qt: 6.10.1

CPython: 3.13.9
PyQt: 6.10.0

Qt wrapper info:
  PyQt6: success
  PyQt5: not imported
  -> selected: PyQt6 (via autoselect)

colorama: 0.4.6
jinja2: 3.1.6
pygments: 2.19.2
yaml: 6.0.3
adblock: 0.6.0
objc: no
PyQt6.QtWebEngineCore: 6.10.0
PyQt6.sip: 6.11.1
pdf.js: no
sqlite: 3.51.0
QtNetwork SSL: OpenSSL 3.5.4 30 Sep 2025

WebExtensions:
  chromium-pdf (mhjfbmdgcfjbbpaeojofohoefgiehjai)
  [x] enabled  [x] loaded  [ ] installed
  /usr/share/qt6/resources/pdf

Style: QFusionStyle
Qt Platform: wayland (Error: Error opening /proc/0/cmdline: [Errno 2] No such file or directory: '/proc/0/cmdline')
OpenGL: Mesa, 3.1 Mesa 25.3.0
Platform: Linux-6.17.9-gentoo-reform2-aarch64-with-glibc2.42, 64bit
Linux distribution: Gentoo Linux (gentoo)
Frozen: False
Imported from /usr/lib/python3.13/site-packages/qutebrowser
Using Python from /usr/bin/python3.13
Qt library executable path: /usr/lib64/qt6/libexec, data path: /usr/share/qt6

Paths:
cache: /home/gordon/.cache/qutebrowser
config: /home/gordon/.config/qutebrowser
data: /home/gordon/.local/share/qutebrowser
runtime: /tmp/gordon-runtime-dir/qutebrowser
system data: /usr/share/qutebrowser

Autoconfig loaded: yes
Config.py: /home/gordon/.config/qutebrowser/config.py has been loaded
Uptime: 0:06:19

Does the bug happen if you start with --temp-basedir?:

Yes, see "How to reproduce".

Description

When content.local_storage is set to false globally, dev tools show white screen even if current website's local storage is enabled using host/URL rule.

How to reproduce

qutebrowser --temp-basedir -s content.local_storage false https://google.com/ :devtools

Points of note

Browser is running on rk3588 arm64 (panthor/panvk) under wayland, does not work with default qtwebengine config, so following env variable has been set:

export QTWEBENGINE_CHROMIUM_FLAGS="--use-gl=disabled --use-vulkan=native --enable-features=Vulkan"

[The-Compiler]

I can reproduce via qutebrowser --temp-basedir -s content.local_storage false ":cmd-later 1000 devtools". Also see #8271.