=== Steps to reproduce
# Open app on iPadOS 18. Ensure iOS Settings are set to light mode.
# Open app Settings > Reading preferences > change to "Light".
# Background app, go to iOS Settings, go to Display & Brightness and choose Dark appearance
# Go back to Wikipedia app.
=== Expected results
Floating tab bar should be frozen on light mode
=== Actual results
Floating tab bar switches to dark mode, but the rest of the app remains on light mode.
=== Screenshots
{F58425223}
=== Environments observed
**App version: ** 7.7.1 (4944) but not a new issue
**OS versions:** 18.3
**Device model:** iPad mini
**Device language:** EN
=== Engineering Notes
We run [[ https://github.com/wikimedia/wikipedia-ios/blob/30681a6e7b92f31d16fa0f56b36e2fd4ffa238f8/Wikipedia/Code/WMFAppViewController.m#L1906 | this code ]] to override the root navigation controllers' user interface style when the user [[ https://github.com/wikimedia/wikipedia-ios/blob/30681a6e7b92f31d16fa0f56b36e2fd4ffa238f8/Wikipedia/Code/WMFAppViewController.m#L1902 | changes their theme ]], as well as when the [[ https://github.com/wikimedia/wikipedia-ios/blob/30681a6e7b92f31d16fa0f56b36e2fd4ffa238f8/Wikipedia/Code/WMFAppViewController.m#L341 | app launches ]]. I think we need try running similar logic at the same moment on WMFAppViewController itself (which is a UITabBarController subclass).
```
NSString *themeName = [NSUserDefaults.standardUserDefaults themeName];
if ([WMFTheme isDefaultThemeName:themeName]) {
self.overrideUserInterfaceStyle = UIUserInterfaceStyleUnspecified;
} else if ([WMFTheme isDarkThemeName:themeName]) {
self.overrideUserInterfaceStyle = UIUserInterfaceStyleDark;
} else {
self.overrideUserInterfaceStyle = UIUserInterfaceStyleLight;
}
```