when drag item from Placeables gui into chest directly. item count in the Placeables gui will not update
edit: more bug
-droping item with 'Z also doesn't update item count
-pick item onto cursor from inventory will decrease Placeables' item count... unlike quickbar that stay the same

I assume these are bugs because item count shouldn't behave different compared to vanilla quickbar

Ah, yeah it seems that my new method of dealing with the players hand was not working at all.
The mod functions completely(Edit: no it didnt lol) back in version 1.1.9, albeit with its own small set of issues.

Factorio's API has a small 'bug' when using the find_empty_stack() function, which is causing my issues.
That bug is now reported here: https://forums.factorio.com/viewtopic.php?f=7&t=106381

I will have to bodge together some workaround until it gets fixed :(

Actually, The transfer from chest is a bug that is seemingly been around for a long time, I will see what i can do about that as well, working on the fix for 'pick item into cursor from inventory' currently. thanks for the info!

Ok, A bunch of underlying issues were fixed, but some remain, specifically when dealing with players hand to/from chests, its a lot harder to capture when those specific events happen.

Is it fixed now as of the latest version?

I believe it should now be fixed, item interactions can be a pain sometimes, but hey every go atleast a bit more of those edge-case bugs are fixed XD