Put the file name in quotes that'll supress any automatic extension.
If you try to save it as
file1.lua it'll end up as file1.lua.txt
If you try to save it as
"file1.lua" it'll end up as file1.lua
If you try to save it as
file1.lua it'll end up as file1.lua.txt
If you try to save it as
"file1.lua" it'll end up as file1.lua
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