How to deal with the windowsill (not the bay window), directly brush latex paint or paste wallpaper?

For windowsills, it is recommended to use windowsills. Because in general, rain or water vapor from glass windows directly drops on latex paint, which easily leads to mildew and rot on the wall. Installing window sills can avoid this problem. Moreover, with the windowsill installed, the daily cleaning work will be much more convenient, and there is no need to worry that the countertop will hide evil people and shelter evil practices, and it will turn black and moldy. The wallpaper is for beauty, but if it is not waterproof, it is recommended to use the windowsill.