<FAB on collapsing toolbar not showing icon when c...

# stackoverflow

[user]

FAB on collapsing toolbar not showing icon when changed after behaviour hide
I have a FAB anchored to collapsing toolbar so when the toolbar collapses the FAB get hidden, when i click the FAB the icon toggles correctly, but after i scroll and the FAB get hidden when i try to change icon it dissapears, but when i collapse and expand the toolbar the icon shows correctly, also i tried invalidating

I have tried change icon with resource and drawable, but i get the same result

Here's a GIF with the problem:
<a...