RoboCopy log needs .txt file extension

I create a RoboCopy log with the switch
/LOG:"path\logfilename" and because I have several command lines, I append
/LOG+:"path\logfilename" to consolidate the RoboCopy log in 1 log file

It always worked, i.e. the RoboCopy log file has a Notepad icon and when I double click the icon, Notepad opens the RoboCopy log file.

But recently, the RoboCopy log file has a generic icon and when I double click the icon, the OS asks what app shall be used and if I choose Notepad, then the RoboCopy log file opens with no problems.

It is thus not a real problem, but it makes me wonder, has anyone else experienced this too?

Anyway, I made the switches more precise by adding the .txt file extension

/LOG:"path\logfilename.txt"
/LOG+:"path\logfilename.txt"

and now the (consolidated) RoboCopy log file has the Notepad icon and upon double clicking the icon, Notepad opens the RoboCopy log file.

Perhaps the switches should have been that way in the first place

Also works with logfilename.log, which can be more helpful if you use search filters a lot when searching disk drives and folders.