I’ve noticed this issue too. Although in my case it’s to do with the act of updating a plugin instead of getting them by opening Studio. I’ve gone ahead and even made a little video demonstrating this problem with a dummy plugin, with as simple-as-can-be coding.
local ToolBar = plugin:CreateToolbar("Empty Test")
local Button = ToolBar:CreateButton("Button","WIP","rbxassetid://2195531164")
print("This is a test!")
plugin.Unloading:Connect(function() print("Unloaded!") end)
I believe this started happening around the same update that allowed for plugins to be independently refreshed instead of needing to refresh the entire list. I’m not certain of the exact version.
This also prevents the plugin function plugin.Unloading from firing, too. Turning off and on the plugin after updating them seems to fix the immediate issue, though will occur again if they need another update.