@ozone10: Nice, thanks!

Thank you for the PR. Once I finish working on my current PR, I'd like to test this one in various scenarios.
By the way, do you plan to support switching between dark and light mode dynamically while the application is running in the future?

@sdottaka
it should be possible, but I am not familiar with MFC, and how WinMerge saves settings. I will probably leave setting implementation to you and provide help if needed.

Thank you for the PR. I’ll merge it temporarily, create a new darkmode branch, revert the changes from master, and continue development in darkmode.

Hi. I've been trying to build the darkmode branch but can't clear all the compile issues. Is there a prebuilt anywhere please?

@dcog989
this branch https://github.com/WinMerge/winmerge/tree/darkmode?
After you switch to that branch, run

git submodule init
git submodule update

You may also need to adjust sdk version since WinMerge is currently using

@ozone10 - thanks very much, I think I followed those instructions and permutations of, but I must be missing something:

function call missing argument list
'getenv': This function or variable may be unsafe. Consider using _dupenv_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS. See online help for details.
Custom build for 'D:\Downloads\winmerge dark 1\winmerge\Src\FilterEngine\FilterLexer.re;D:\Downloads\winmerge dark 1\winmerge\Src\FilterEngine\FilterParser.y' exited with code 9009.
Custom build for 'D:\Downloads\winmerge dark 1\winmerge\Src\FilterEngine\FilterLexer.re;D:\Downloads\winmerge dark 1\winmerge\Src\FilterEngine\FilterParser.y' exited with code 9009.	

I'm still running one of the builds from your testing, was hoping to update, but it's not essential.

@dcog989
Running DownloadDeps.cmd in the WinMerge directory should download the tools needed to process FilterParser.y, which will likely resolve the build error.

hey. thanks, that moved things forward but stuck with:

Custom build for 'D:\Downloads\winmerge dark 1\winmerge\Src\FilterEngine\FilterLexer.re;D:\Downloads\winmerge dark 1\winmerge\Src\FilterEngine\FilterParser.y' exited with code 9009.

Something to do with flex / bison missing??? I added https://github.com/lexxmark/winflexbison/releases/tag/v2.5.25 to path but that didn't help.

It seems DownloadDeps.cmd does not work properly if the folder name contains spaces, such as “winmerge dark 1.” Please try using a folder name without spaces.

That did it! Many thanks. :)

@ozone10
Since statically linking an MPL-2.0 library with WinMerge (GPLv2-or-later) could cause license conflicts, we forked darkmodelib
and built it as a DLL. We now use this DLL dynamically to ensure license compatibility.

@sdottaka
there should be no conflict. I don't use Exhibit B - “Incompatible With Secondary Licenses” Notice, so it can be linked statically without issue.

@ozone10

You're right — according to GNU’s license list, there’s no issue. Sorry for the confusion; I trusted an AI answer without checking carefully. That said, I’ll probably keep using the DLL, since it also allows the x86 build of WinMerge to support DarkMode. (The x86 build still supports Windows XP and uses an older SDK, which fails to compile darkmodelib from source.)

@sdottaka
I took inspiration from your fork with DLL commits. Unfortunately I might have introduced some conflicts for you, I am sorry.
My goal was to make it easier to use GetProcAdress / LoadLibrary for explicit loading and option to change DLLs without needs to recompile whole app.