Dark Mode style for UDL

dfs-

Is it possible for a user-defined language to include additional information for dark mode?

Currently my UDL describes colors that are good for light mode (= white canvas/background)…

…but are hard to read in dark mode (= greyish canvas/background)…

Finding a middle ground seems quite hard, so I wondered if it is possible to modify the style for the dark mode the same way it works for the included languages?

Notepad++ v8.9.2   (64-bit)
Build time: Feb 13 2026 - 02:47:53
Scintilla/Lexilla included: 5.5.8/5.4.6
Boost Regex included: 1_90
pugixml included: 1.15
nlohmann JSON included: 3.12.0
Path: C:\Program Files\Notepad++\notepad++.exe
Command Line: C:\Development\GIT\SWLLIS\dbsystem\dbcreate\Befund\befundauftrag.pro 
Admin mode: OFF
Local Conf mode: OFF
Cloud Config: OFF
Periodic Backup: OFF
Placeholders: OFF
Scintilla Rendering Mode: SC_TECHNOLOGY_DEFAULT (0)
Multi-instance Mode: monoInst
asNotepad: OFF
File Status Auto-Detection: cdEnabledNew (for current file/tab only)
Dark Mode: ON
Display Info:
    primary monitor: 1920x1080, scaling 100%
    visible monitors count: 3
    installed Display Class adapters: 
        0000: Description - Intel(R) Iris(R) Xe Graphics
        0000: DriverVersion - 32.0.101.7077
        0001: Description - Microsoft Remote Display Adapter
        0001: DriverVersion - 10.0.19041.5794
        0002: Description - Microsoft Remote Display Adapter
        0002: DriverVersion - 10.0.19041.5794
OS Name: Windows 10 Pro (64-bit)
OS Version: 22H2
OS Build: 19045.6456
Current ANSI codepage: 1252
Plugins: 
    ComparePlus (2.2)
    ElasticTabstops (1.5)
    JSMinNPP (1.2312)
    mimeTools (3.1)
    NppConverter (4.7)
    NppExport (0.4)
    PlantUMLViewer (1.9.0.13)
    PythonScript (2)
    XMLTools (3.1.1.13)

PeterJones

@dfs said in Dark Mode style for UDL:

I wondered if it is possible to modify the style for the dark mode the same way it works for the included languages

You define two separate UDL (two separate files), one with your light colors, one with your dark colors. Then, as is done in markdown._preinstalled_DM.udl.xml (which comes preinstalled when you get N++), you set darkModeTheme="yes":

<UserLang name="Markdown (preinstalled dark mode)" ext="md markdown" darkModeTheme="yes" udlVersion="2.1">

(yours would, of course, have the name and extensions appropriate for your UDL)

When you have both those UDL in Notepad++, then when it’s in Dark Mode, it will use the settings from the UDL with darkModeTheme="yes", and when in Light Mode, it will use the settings from the UDL without that attribute (or with that attribute set to "no", IIRC).