nativeTheme not receiving updated event respecting Linux system preference change

[davidwinter]

Preflight Checklist

• I have read the Contributing Guidelines for this project.
• I agree to follow the Code of Conduct that this project adheres to.
• I have searched the issue tracker for an issue that matches the one I want to file, without success.

Issue Details

• Electron Version:
  • 10.1.3 11.0.1
• Operating System:
  • Ubuntu 20.04 x64

Expected Behavior

When switching "Window theme" preference between Light and Dark modes on Ubuntu, the updated event should be triggered for nativeTheme.

Actual Behavior

The updated event is never triggered when alternating between window themes.

To Reproduce

See: https://github.com/davidwinter/electron-native-theme/blob/master/main.js

$ git clone https://github.com/davidwinter/electron-native-theme.git
$ yarn
$ ./node_modules/.bin/electron main.js

Screenshots

[ckerr]

I think this is fixed as a side-effect of #23479

[davidwinter]

This is still broken with 11.0.1 @ckerr

Example repo updated.

[shiftkey]

I'm seeing similar behaviour on Ubuntu 20.04 with Electron 11.1.1 while working with GitHub Desktop's Linux fork. I can put together a better repro but the short version:

• changing from Yaru-light to Yaru-dark does update the default chrome of the app
• querying from the console for nativeTheme.shouldUseDarkColors shows the correct value
• but the updated event on nativeTheme doesn't fire, so the app content itself is unable to switch from light to dark as the OS changes

This limits us being able to emulate the "Automatically switch theme to match system theme" behaviour that macOS and Windows now allow us to do in the app.

[julianfairfax]

Hopefully this can be resolved somehow. I use an extension to change my theme automatically depending on time of day, and Electron apps (most of my apps) use the system theme when launching, but as mentioned don't update it after the theme has been changed, and they require a relaunch.

[ffflorian]

Also doesn't work with 11.4.1 and 12.0.1, but seems to be fixed with 13.0.0-beta.7. 🎉

[julianfairfax]

Also doesn't work with 11.4.1 and 12.0.1, but seems to be fixed with 13.0.0-beta.7. 🎉

Is there any indication of when version 13 will be released? And will the electron apps I use have to each be individually updated by their developer?

[ffflorian]

@julian-fairfax

Is there any indication of when version 13 will be released?

Electron 13 stable release is scheduled for 2021-05-25.

And will the electron apps I use have to each be individually updated by their developer?

Yes.

[Nantris]

Any hope for a backport on this fix, to at least 11.x?

@shiftkey's finding that the value is updated but 'updated' event is never triggered is interesting. That seems not to be the case for me on Mint 20.1 xfce.

For us the value of nativeTheme.shouldUseDarkColors seems to be defined at the first run of the main process and doesn't change after that. If we create new windows, we will still get the old value if we run something like this in devtools: window.matchMedia('(prefers-color-scheme: dark)')

[Nantris]

Anybody on the team know what PR may have resolved the issue for @ffflorian and whether it might be backport-able?

[nornagon]

Closing this as fixed, but feel free to continue discussing backports.

[aykevl]

Unfortunately, this doesn't appear to be working on KDE (current Arch Linux ARM / Asahi Linux, KDE Plasma 5.25.5). Most other applications do automatically update when the theme changes, including all tested KDE apps, Firefox, and Inkscape (GIMP and Chromium don't). The correct theme is applied on startup, but doesn't get updated when the system theme changes.