actions - change extension
what is there to know about changing the extension? well, the main question is where do you want to add this extension you
typed into the text box? what are the options?
replace the existing extension.
add a new one after the existing extension (e.g you want to install new files and rename all the existing ones to
filename.ext.old)
add some characters to the exicting extension - at the begining or the end of it.
it's true that the last two are similar. the difference is only the dot.