iPadOS 18 fixes this issue. Now, when using iPhone apps on an iPad with an external keyboard, pressing Control + Command + Space will open an emoji selection menu, just like in apps optimized for iPad. This update makes it easier for users, especially those on social networks, where there is no dedicated version for iPadOS.
iPadOS 18 will add many of the features that came with iOS 18, including new ways to customize the Home screen, a redesigned Control Center, and a Calculator app.
iPadOS 18 is currently in beta and is scheduled for official release in the fall.
Source: Ferra

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