When I start to spam a macro, I get his popup that won't go away. Tried several different macros.

Message: Usage: local result = C_Item.IsEquippableItem(itemInfo)
Time: Thu Apr 18 11:41:06 2024
Count: 16
Stack: Usage: local result = C_Item.IsEquippableItem(itemInfo)
[string "=[C]"]: in function IsEquippableItem' [string "@Interface/SharedXML/Chat/ChatFrame.lua"]:1048: in function <Interface/SharedXML/Chat/ChatFrame.lua:982> [string "@Interface/SharedXML/Chat/ChatFrame.lua"]:1275: in function ?'
[string "@Interface/SharedXML/Chat/ChatFrame.lua"]:5388: in function <Interface/SharedXML/Chat/ChatFrame.lua:5354>
[string "=[C]"]: in function ChatEdit_ParseText' [string "@Interface/SharedXML/Chat/ChatFrame.lua"]:5065: in function <Interface/SharedXML/Chat/ChatFrame.lua:5064> [string "=[C]"]: in function ChatEdit_SendText'
[string "@Interface/SharedXML/Chat/ChatFrame.lua"]:3246: in function <Interface/SharedXML/Chat/ChatFrame.lua:3240>
[string "=[C]"]: in function RunMacroText' [string "@Interface/FrameXML/SecureTemplates.lua"]:468: in function handler'
[string "@Interface/FrameXML/SecureTemplates.lua"]:690: in function <Interface/FrameXML/SecureTemplates.lua:672>
[string "@Interface/FrameXML/SecureTemplates.lua"]:704: in function <Interface/FrameXML/SecureTemplates.lua:697>
...
[string "=[C]"]: in function ChatEdit_SendText' [string "@Interface/SharedXML/Chat/ChatFrame.lua"]:3246: in function <Interface/SharedXML/Chat/ChatFrame.lua:3240> [string "=[C]"]: in function UseAction'
[string "@Interface/FrameXML/SecureTemplates.lua"]:364: in function handler' [string "@Interface/FrameXML/SecureTemplates.lua"]:690: in function <Interface/FrameXML/SecureTemplates.lua:672> [string "@Interface/FrameXML/SecureTemplates.lua"]:704: in function <Interface/FrameXML/SecureTemplates.lua:697> [string "@Interface/FrameXML/SecureTemplates.lua"]:746: in function SecureActionButton_OnClick'
[string "@Interface/FrameXML/ActionButton.lua"]:100: in function TryUseActionButton' [string "@Interface/FrameXML/ActionButton.lua"]:135: in function ActionButtonDown'
[string "ACTIONBUTTON11"]:2: in function <[string "ACTIONBUTTON11"]:1>

Locals: (*temporary) = "Usage: local result = C_Item.IsEquippableItem(itemInfo)"

This isn’t a GSE bug but a WoW bug. You have a line in your template that is trying to call a talent you don’t know.

The solution is to check that all the spells on a line are known.

For example for hunters this is super triggerable:
/castsequence [nomod,known:120679,nochanneling,combat] reset=combat Bloodshed, Dire Beast, Dire Beast; [nomod,nochanneling,combat,known:321530] Bloodshed it is possible to not know both Dire Beast and Bloodshed.

If you take out the second known so its just /castsequence [nomod,known:120679,nochanneling,combat] reset=combat Bloodshed, Dire Beast, Dire Beast; [nomod,nochanneling,combat] Bloodshed It will throw this error.