How to find out which version of the .NET Framework an executable needs to run?

Question

Using Notepad, three decades old, 200kb in size, preinstalled tool:

open application with notepad appname.exe,
search for word framework,
repeat last search with F3 until .NET Framework,version=vX.Y shows up
if nothing found (versions below 3.0) search for v2. … still 100 times easier then installing gigabytes of dot net analyzer tools and garbage studios.

update: Thought and Marcus suggested in comments that search term could also be netstandard or netframework