UI Customisation
Stirling PDF allows straightforward customization of the application name and appearance to make Stirling PDF your own.
Application Name Settings
This setting controls the application name:
appNameNavbar- Used as the browser tab title and as the issuer name shown in authenticator apps for two-factor (TOTP) login. Despite its name it is not shown in the navigation bar (which displays the logo), so do not leave it blank if you use TOTP. Empty falls back to "Stirling PDF".
Show update notifications
These settings (in Settings.yml) control system behavior and customization capabilities:
showUpdate- Controls whether update notifications are displayedshowUpdateOnlyAdmin- When true, restricts update notifications to admin users only (requiresshowUpdate: true)
UI Customization Options
In-App Settings Management (Recommended)
If you have login enabled and are logged in as an admin, you can configure all settings directly in the application through the Settings menu. No need to edit settings.yml manually!
How to access:
- Enable login:
SECURITY_ENABLELOGIN=true - Log in as an admin user
- Navigate to Settings in the application
- Configure all options through the UI
- Changes apply immediately
Available customizations:
- Application name and branding
- Update notification settings
- Language settings
- Theme preferences
- Logo style (classic/modern)
To replace the bundled logo with your own, see Static File Overrides - you drop your logo files into customFiles/static/<style>-logo/ and they replace the built-in ones.
Static File Overrides (Advanced)
For customization beyond the built-in settings, you can override static files like logos, favicons, and images:
services:
stirling-pdf:
image: stirlingtools/stirling-pdf:latest
ports:
- '8080:8080'
volumes:
- ./customFiles:/customFiles:rw
Then place your custom files in customFiles/static/ matching the path structure. Common examples:
customFiles/static/favicon.svg- Custom faviconcustomFiles/static/classic-logo/logo.svg- Custom logocustomFiles/static/modern-logo/logo.svg- Custom modern logo
Learn more: Other Customisations - Static File Overrides
Injecting Custom CSS
Stirling PDF does not have a "drop a CSS file here" setting - the bundled index.html doesn't reference an extension stylesheet, so a customFiles/static/custom.css on its own won't load. To inject CSS you need to provide your own copy of index.html that links to your stylesheet.
This is the right approach for things like:
- Tweaking colors or fonts beyond what theme settings cover
- Overriding component z-index values (e.g. lifting the Google Drive Picker above modal overlays)
- Hiding specific UI elements
- Embedding tracking / analytics snippets in
<head>
Recipe
1. Drop your CSS file into customFiles/static/
customFiles/
└── static/
└── custom.css
It will be served at /custom.css (or under your configured root path if you've set SYSTEM_ROOTURIPATH).
2. Get a copy of the current bundled index.html
The easiest way is to copy it out of a running container:
docker cp stirling-pdf:/app/BOOT-INF/classes/static/index.html ./customFiles/static/index.html
If that path doesn't exist on a future release (e.g. a layered JAR layout), try /app/app.jar instead and extract BOOT-INF/classes/static/index.html from it with unzip. The endpoint location is what matters - any equivalent copy of the served index.html works.
3. Add your stylesheet link
Open customFiles/static/index.html and insert a <link> immediately before </head>:
<link rel="stylesheet" href="/custom.css">
</head>
4. Restart Stirling PDF
On the next boot, the log will show:
Using custom index.html from: /customFiles/static/index.html
Your stylesheet now loads on every page.
index.html after every Stirling PDF upgradeThe bundled index.html references hashed JS/CSS asset filenames (e.g. index-fSaGHxPC.js) that change on every release. Your override will reference stale filenames after an upgrade and break the UI. Repeat step 2 (copy the new index.html and re-add your <link>) after each upgrade, or automate it with a small script in your deployment pipeline.
Worked example - lift the Google Drive Picker above modal overlays
The file manager modal sits at z-index: 1200. The Google Drive picker, rendered by Google's own scripts, doesn't always respect this. Force its iframe overlay higher:
/* customFiles/static/custom.css */
.picker-dialog,
.picker-dialog-bg {
z-index: 9999 !important;
}
After completing the recipe above, restart and the picker now floats over the file manager.
Fork the Frontend (Developers)
For deeper customization than CSS can express (changing layouts, replacing components, adding new tools):
- Clone the Stirling PDF repository
- Modify the React components in
frontend/editor/src/ - Build from the repo root:
cd frontend && npm ci, thentask frontend:build:proprietary(or pass-PbuildWithFrontend=trueto the gradle build) - Output appears in
frontend/editor/dist/ - Copy the built artifacts into
customFiles/static/and restart, or build your own Docker image
This approach requires maintaining your fork and manually merging updates.
Configuration Examples
- Settings File
- Local Environment
- Docker Run
- Docker Compose
ui:
appNameNavbar: navbarName # Browser tab title and TOTP issuer label (not the navbar)
system:
showUpdate: false # Control update notification visibility
showUpdateOnlyAdmin: false # Restrict update notifications to admins
You can configure the UI and system settings in two ways when running locally:
Option 1: Using Java Properties
java -jar Stirling-PDF.jar \
-DUI_APPNAMENAVBAR="Stirling PDF" \
-DSHOW_UPDATE=false \
-DSHOW_UPDATE_ONLY_ADMIN=false
Option 2: Using Environment Variables
export UI_APPNAMENAVBAR="Stirling PDF"
export SYSTEM_SHOWUPDATE=false
export SYSTEM_SHOWUPDATEONLYADMIN=false
-e UI_APPNAMENAVBAR=Stirling PDF \
-e SYSTEM_SHOWUPDATE=false \
-e SYSTEM_SHOWUPDATEONLYADMIN=false
environment:
UI_APPNAMENAVBAR: Stirling PDF
SYSTEM_SHOWUPDATE: "false"
SYSTEM_SHOWUPDATEONLYADMIN: "false"