want to set item to images but it show blank instead

Hello all,
i have a weird problem with your library which is really great one and ease my work; i would like to know if its possible to put a png with colors and preserve these color on an item of your navigation bar ? if so how to attempt it ;is there a size requirement ?
Thanks

Start by reproducing the blank PNG behavior with a colored image used as a bottom-navigation item, checking whether the issue is related to image size or color handling. Done means identifying the supported image behavior and either making the colored PNG display correctly or documenting the limitation and required usage.

Written by the indexing model from the issue text.