My friend and I both encountered the same bug in our respective saves within a day of each other. In my case, I was diving and caught a lobster but had a full inventory. Went to trash some stone to make room for the sea creature and the stone started stuttering and I couldn't leave my inventory. I believe the same thing happened to her but when catching a bug on land. Standing over the item while trying to do the inventory tweaking is what seems to cause it. Has only happened once to me (by end of winter, year 1) and once to my friend (summer, year 1).
Both issues were on Steam
Game Version 1.1-1226
Keyboard/Mouse
My save file is attached
#Bug when inventory is full and attempting to trash item
valid peak
Not sure if this sent properly since I can see my message in the thread preview but not here 
rain yew
Hello @valid peak. We appreciate the report!