Add option to have app icon with white background and other changes for iOS 18 app icon support

[willfs84]

Add option to have the app icon background white instead of the current dark app icon background only. And perhaps even consider making the white background app icon as the default (see below for why).

I know this may seem like a silly low priority issue but when Apple revealed iOS 18, I was surprised to see so many people hating the new dark app icons so strongly. Which made me think that Firefox for iOS app icon being dark-only probably isn't doing it any favours. It seems a lot of people really care about the way their app icons and home screens look and it's very important to them, so giving them this option is worth the effort.

I selected "bug" instead of "feature request" because as far as I can tell, by the way Apple's new automatic app icon theming logic works in iOS 18, it seems like it's designed with the assumption that app icons have a white background by default, and then it automatically changes it to dark if the user has selected dark mode. But it doesn't work the other way around (meaning if an app icon is only available with a dark background as is the case with Firefox, it doesn't appear that it can automatically turn it into a white background). https://medium.com/@GuillemBruix/design-your-dark-and-tinted-versions-of-your-app-icon-for-ios-18-827444a31851#:~:text=What%20does%20this%20mean%20for%20app%20designers%20and%20developers%3F

https://mastodon.social/@_inside/112779930099702850

Worth noting that Firefox on iOS is the only major browser that doesn't have a white background

┆Issue is synchronized with this Jira Task

[taze55]

I would appreciate it if you could handle the widget in the same way.

[data-sync-user]

➤ Norberto Andres Furlan commented:

gangadi can you take a look to this one?

[willfs84]

Also, even when the user has chosen dark icons, Firefox doesn't match all the other icons because its dark background is baked in (it has a blue/purple tinge and no gradient).