Browser support for the inputmode attribute has improved and is now above 90% globally (mainly because most people are using Chrome or browsers with Chromium-based engines - Safari does not support it at all for some reason ). Either way, even if the attribute is not supported by the browser, it will simply be ignored. For the rest of the world though the result is better UX, especially for mobile devices and when using virtual keyboards, because of the automatic selection of an appropriate keyboard type.

inputmode

The inputmode global attribute is an enumerated attribute that hints at the type of data that might be entered by the user while editing the element or its contents. This allows a browser to display an appropriate virtual keyboard.

GitHub Issue #: 
5964